Quarry is terribly undersized here, but he has always impressed me, even in defeat. The size disparity might be too much to overcome, though.
Quarry did will vs big punchers like Mac Foster , Shavers and the like but Cooney could chop you like did Dino Dennis and Jerry I think lose on Cuts.
Quarry was hell on big men. Cooney might stop him, but I think Quarry by clear decision is more likely.
Quarry will need to box some. If he actually goes "toe-to-toe" with Cooney, then Cooney's long range hooks will connect too often.
I know the popular answer here is Quarry, but the size is too much of a difference here. Cooney would ko QuARRY IN 6 when Quarry was about to make a comeback in the early 80s he had a sparring session(according to a good source and friend of mine) with Gerry Cooney and Quarry told the source he had never been hit like that in his life,session was stopped shortly after. I think Cooney gets underrated on these fantasy matchups.
If Quarry shows up at his best, he makes Cooney look foolish. Most likely a decision win or a late stoppage as he grinds him down. Cooney isn't that much better than Mac Foster or Ron Lyle, just another tough limited power puncher for Quarry to take apart.