IIRC SSG Goku and Beerus were still going to cause the destruction of the universe, the only reason they aren't 3-A is due to the timeframe being unknown. The Dragon World is 110x the size of the observable universe.
How long it would take is unknown, but it would have occurred within the course of the battle itself, so I imagine a few minutes in-universe, at most?
In which case, SSG Goku would easily be capable of destroying the observable universe which comprises of 2 trillion galaxies. If we factor in that the Dragon World is at least 110x that, we come to SSG Goku being capable of destroying 220 trillion galaxies over time.
I honestly have no clue why Goku isn't 3-A in SSG, by virtue of the fact that he would have eventually destroyed a universe 110x our own, and the only metric for 3-A is destroying the observable universe but, whatever.
Regardless, 3-B is 2x 3-C at minimum it seems. This means SSG Goku is around 110 trillion times baseline 3-B overtime and should, realistically, be 3-A.
Manga SSB is about 10x more powerful than SSG, making RoF Goku at least 1.1 quadrillion times 3-B. If we assume his power-stressed Blue is 2x (like a base Kaio-Ken) then he would hit 2.2 quadrillion times baseline, and both -Sign- and UI are stronger than that.
- Manga SSG = 110 trillion times 3-B (overtime)
- Manga SSB = at least 1.1 quadrillion times 3-B (overtime)
- Manga SSBKK (similar to KK) = at least 2.2 quadrillion times 3-B (overtime)
- Manga UIS = unquantifiably above SSBKK
- Manga UI = unquantifiably above UIS
Is my overall answer. This is assuming Goku's base power barely increased since BoG.