I have Goku with an almost 35% advantage by numbers.
Kamiccolo: 500
20%: 100
Goku SSJ: 150
So Goku spanks
Note: the gap for me is pretty much the Same gap ginyu claimed would be enough to trash the ginyu force, which is a 40k confront of a 60k kinda gap
I agree with this being closer to 50% in order for it to be a decent fight. Goku wins imo. But I am speaking off the top of my head and not doing any heavy calculations or anything.
From memory, my latest rendition of Piccolo fell around 700-750mil, so at its highest 20% would be 150mil, making this a damn good match that I'd give to Goku unless Piccolo pulls out a Gekiretsu Kodan.