November 3rd Update

I finally was able to come up with concrete power level models for Dragon Ball Z characters. The points used were:
5, 97.2 J/s (Normal Human)
260, 4.18e+15 J/s (King Piccolo having the power of a nuclear bomb)
18000, 2.4e+32 J/s (Vegeta Saiyan Saga/Cui being able to destroy Earth)
530000, 1e+37 (Frieza's first form being capable of destroying Jupiter)
Using a Polynomial model, the equation for the destructive power a DBZ character can muster is:

y = 7E+19x^3 - 5E+23x^2 + 1E+26x - 4E+30
Where x is the character's Battle Power on the scouter system and y is the destructive power in Joules/sec. This places Goku's initial Super Saiyan transformation at 2.362e+44 Joules/sec. So Super Saiyan Goku alone hits 11,290,630 times harder than Superman's max estimated Infinite Mass Punch.

The Power model gives the equation of:

y = 0.0103(x^7.2513). According to Microsoft Excel's R-Squared, this model is .9743, or 97.43% accurate. My father who has decades of experience in quality management informs me that anything above .6 or 60% is a good fit.

Which would give Goku's initial Super Saiyan power level of 150,000,000 have the destructive power of 6.573e+57 Joules/sec.

If it takes 2.129656e+47 Joules to destroy a solar system, and there are 100 Billion solar systems in a galaxy, Superman's highest feat of durability gives him the ability to survive 1.064e+58 Joules.

Since Super Saiyan God is at least 144 times more powerful than the initial Super Saiyan transformation, SSG Goku has the destructive power of 9.46512e+59 Joules. Therefore, Super Saiyan God is nearly 89 times more powerful than Superman's most impressive feat of durability.

Also, I found out that Superman got control over his mental inhibitions in the comics around 1999. The Sun Eater explosion was mentioned in a comic in 2007. Ergo, Superman was not holding himself back when he was hurt by it, so any equivalent force could knock him out.

Other calculations demonstrating Goku would win

Diameter of the sun = 864,575.9 miles

Surface area of Superman's body = 2.39 square meters

Minimum length of a Sun Eater: 2,000 miles

Surface Area of the Earth: 510,000,000 sq kilometers

Superman per sq kilometer: 418.41004184100418

Energy needed to destroy Earth: 2.4 * 10^32 joules

Galaxies in the universe > 100 Billion

Power Level sufficient to destroy Earth: 53,000 (530,000 is capable of destroying a planet with 10x Earth's Gravity in 1 attack) 7,900 better reflects this

Energy of a supernova: 2 * 10^44 joules

Flight Speed of Goku's return flight down Snake Way: 13,018 mph (for the sake of accounting for the non-linear distance of Snake Way and for the sake of giving Superman more of an advantage, we will say this requires a Power Level of 18,000)

Power Level of Goku's normal Super Saiyan form > 150,000,000

Speed of Light: 669,600,000 mph
Goku's weight: 62 kilograms
Superman's weight: 107 kg
Goku's movement efficiency advantage: 72.58%
ABSOLUTE MAX for Superman's Infinite Mass Punch: 2.092e+37 Joules

How I calculate joules per second: Piccolo's initial charging time of the Makankosappo/Special Beam Cannon was 5 minutes (300 seconds). The attack was three times his power level, so therefore at a minimum, a DBZ character can muster the full force of their power level every 100 seconds.

Full Power Super Saiyan = 3x SSJ (or 2x ASSJ [=1.5x SSJ]) Vegeta actually was said to be 3x stronger than his base SSJ in ASSJ, though this was also due to increase in base from training in the HTC/ROSAT

SSJII: 2x FPSSJ

Super Perfect Cell is close to SSJII. His Solar Kamehameha was said to be able to destroy the Solar System. To compromise with Xenomaster, I'll reduce that feat to being able to destroy the sun. That would take over 2.277 * 10^41 joules. I feel this is more than fair as destroying the Solar System would apparently be greater than a supernova (5.09 * 10^37 Tons of TNT * 4.184 * 10^9 joules/ton of TNT, so that would be 2.129656 * 10^47 joules. So Xenomaster, I'm nerfing the capabilities of Super Saiyan 2 by OVER NINE HUNDRED THOUSAND times (935290.2942468 to be exact) what DBZ fans would give it.)

SSJIII: 4x SSJII

SSG: 6x SSJIII (Beerus surpassed Goku's SSJIII at less than 10% of his full power. Toriyama lists SSG as a 6 with Beerus as 10.
Therefore, SSG is more than 144 times the basic SSJ transformation in power.
Using 53,000 as the power level needed to destroy Earth, SSG would at an ABSOLUTE MINIMUM be able to muster 9.781132 * 10^37 by a faulty calculation of mine that made it so that it only takes ten times the power to destroy a planet with ten times the gravity of earth. Earth has 6.04 times the moon's gravity, and it would take 1833.3333 times the force needed to destroy the moon in order to destroy earth. Jupiter has 2.567666 times the Earth's gravity, but it would take 41,666.666667 times the force needed to destroy earth to destroy Jupiter.

So actually, the ABSOLUTE MINIMUM for Super Saiyan God Goku's full power attack would be 4.075e+41 Joules. If you agree that Super Perfect Cell could have at least destroyed the Sun with the Solar Kamehameha, that would be the minimum of 5.4648 * 10^42 joules.

Also, Beerus is capable of destroying entire solar systems with ease, and the entire universe at full power. Now, to give the Superman fans no room to complain, I'll reduce that to Beerus being able to destroy an entire galaxy at full power. There are as many as 100 Billion Solar Systems in our galaxy, so we can easily say Goku's Super Saiyan God transformation can destroy 10 Billion solar systems. But instead, for the sake of argument, I'm not even giving SSG Goku the ability to destroy 1 solar system)

So at the absolute minimum, Goku in his Super Saiyan God form would be able to muster 1:2,044,753.1021-th (4.890566e-7) of a supernova.

Plus, Superman didn't even survive the whole of the Sun Eater explosion.

And by the way, for my calculations, I had Superman right up in the face of the Sun Eater explosion, when in reality he was easily tens of millions of miles away and assuming the Sun Eater had the absolute minimum diameter. So I gave Superman a 249,2016,349.2063492-fold increase in durability, plus assumed he stuck around for the whole thing - which it is said he would have DIED if he had right in the comic. Goku still wins.

On a side note, if Superman was able to use 100% of the Solar Energy he absorbed, even if he absorbed ALL of the energy of our sun outputs each second (3.8*10^26 joules), Vegeta IN HIS INITIAL APPEARANCE is stronger than that with a MINIMUM of 8.1509433952 * 10^31 joules with a Power Level of 530000 being capable of destroying a planet with 10 times Earth's gravity. It actually takes much more than 10 times the power to destroy a planet with 10 times the gravity, it would actually be 67.69 times the force at absolute minimum. Jupiter, which only has about 2.5 times Earth's gravity, would easily need a thousand times the power, but I'm reducing it to 10 goes in Superman's favor if anything. But it proves that YES Xenomaster, Vegeta CAN destroy Earth in one blast.

As Xenomaster was kind enough to point out, Superman's most impressive feat of durability is not dying after absorbing enough anti-sunlight to destroy half a galaxy. Well, I already commented that Beerus is said to be able to destroy the whole universe at full power. Again, let's reduce that by a factor of tens of billions and say it's only 1 galaxy. Goku's Super Saiyan God in Battle of the Gods is ranked at around a 6 by Akira Toriyama while Beerus is at a 10.

And really, it can be inferred that the Man of Steel was able to absorb the anti-sunlight like he does normal sunlight. That's still an impressive feat considering another version of Superman was killed by overcharging using the normal sun. But that's still like saying Superman has a big enough capacity to store energy that he can't be killed by making him stronger.

But Superman has shown durability greater than the 50x supernova, though nowhere close to being in the proximity of a supernova concentrated to the diameter of the Sun Eater point blank (which still is less than the minimum force calculated for a SSG Goku Full Power attack), the maximum someone who actually knew how to calculate relativistic mass calculated Superman's Infinite Mass Punch.
screwattack.roosterteeth.com/p…

Superman WILL BE KNOCKED OUT by a blow with a force 5 sextillion megatons, and as little as 30 trillion megatons. 
So a force between 2.092e+28 and 2.092e+37 Joules is a CONFIRMED KNOCK OUT for Superman. This is consistent with UberHulk's observation that

Planetary level attacks i.e. those capable of destroying a planet consistently knock out Superman. While he may survive the impact he is rendered unconscious...

By the way, that lower limit is possibly reachable by, get this, MASTER ROSHI.

Now I know what you're thinking, that can't be right. Master Roshi can dish out as much punishment as Superman's Infinite Mass Punch?! It's crazy I know, but as Master Roshi destroyed the moon in the original Dragon Ball manga, that means a character with a power level of 138 can muster 1.309309309e+29 Joules of energy.

But Power Levels are Bullshit, everyone knows. Indeed, but that's why this minimum estimation of Goku's SSG abilities being shown to surpass Superman's known feats of durability (if you exclude absorbing the anti-sunlight, but even if Superman didn't get a power boost from absorbing it, it was as Superman says in the comic, he can absorb sunlight, so why not anti-sunlight?) is basically irrefutable.

Power Levels are NOT Linear

An average human, (Power Level 5) has an output of 97.2 Joules/sec. King Piccolo (Power Level 260) was tossing around the force of a nuclear weapon (4.18e+15 Joules) wiping out an entire country without breaking a sweat. Saiyan Saga Vegeta (Power Level 18000) could have destroyed the Earth (2.4e+32 Joules).

However, the improved forms of Super Saiyan do mention being a certain multiple of previous forms, so we can treat FPSSJ and beyond as being linear from the initial Super Saiyan Transformation, which was treated as 150,000,000 for the sake of having an irrefutable base for Goku.
We know that First Form Frieza was able to destroy a planet with 10 times Earth's gravity. So then we can, for the sake of not giving the Superman fans any right to complain, say that First Form Frieza could destroy Jupiter (2.56 times earth's gravity, 1e+37 Joules to destroy). Using Vegeta as an Earth destroyer, a very reasonable estimate for the increase in destructive power for DB characters using the Scouter's numeric system, the formula for the destructive power is as such:

Coefficient for destructive power increase: (1e+37/2.4e+32) /(530000/18000) = 1415.0943587*(Higher Power Level/Lower Power Level)*(Joules of the Lower Power Level)

Therefore, a much more accurate measure of the base Super Saiyan (Battle Power 150 Million)'s destructive power would be 4.0049839e+42 Joules, or 4.0049839e+40 Joules/second using the Piccolo rule of a DBZ character being able to output their full power every 100 seconds at a minimum. Since Super Saiyan God is at the ABSOLUTE MINIMUM 144 times more powerful than 150 Million, the ABSOLUTE MINIMUM with proper calculation would be 5.7671e+42 Joules/sec.

So the MINIMUM ESTIMATE of SSG Goku can hit 275,673.996 times harder than the MAXIMUM ESTIMATE for Superman.

And that was against a moon. Compared to that, hitting the broad side of a barn seem like trying to pin a fly to the wall with arrows and not kill it. Goku would be moving significantly faster than the moon too (and using 72.58% less energy to move around than Superman). Indeed, there is a distinct possibility that Goku would be able to dodge the Infinite Mass Punch altogether.

There are around 100 Billion solar systems in our galaxy. Half a galaxy would be 50 Billion (5e+10) solar systems, therefore, Superman's ABSOLUTE MAX of durability would be 1.064828e+58 Joules. Now, using the ABSOLUTE MINIMUM for SSG Goku (using Cell as a Solar System destroying attack) would be 5.111e+48 Joules.
But! Like Power Levels, Superman's absorption of sunlight is NOT LINEAR either. If Superman soaked up EVERY DROP of energy from our sun, he would only have 3.8e+26 Joules/second. Only a billionth of the Sun's energy reaches earth (3.8e+17 Joules/sec). 

Since Superman's energy output would be between 1.4686767e+34 and 2.092e+37 Joules, Superman gets billions of times more than 3.8649e+16 and 5.505e+19 from yellow sun energy.
So it stands to reason that with ANTI-SUNLIGHT, that instead of multiplying the damage, the damage would be divided by that multiplier. Thus, enough anti-sunlight to destroy half a galaxy would "only" be 2.755e+41 Joules worth of energy. That's less than what it takes to destroy a Solar System, something that Super Saiyan God Goku can do with ease by virtue of being 60% of Beerus's universe-destroying full power. (Super Perfect Cell/SSJII is thought capable of destroying an entire solar system by DBZ fans by the way)


Thus, the ABSOLUTE MINIMUM of an attack at SSG Goku's full power 4.075e+41 is 47.93% beyond a calculated ABSOLUTE MAXIMUM for Superman's durability. Hey, I was going to write the anti-sunlight off as something Superman could just absorb without it actually hurting him. But if you want to say that Superman was damaged by the whole thing, then I'm going to insist that you at least give Goku the ability to destroy a single galaxy, which would be 1:6e+10 th of his capabilities according to official sources.

 

Shame on you Wizard and Boomstick for not taking the time to properly calculate things.

Resources:
www.madsci.org/posts/archives/2001-11/1004909251.As.r.html