If Simon survives the early onslaught (and that's a big if) I could see him stopping Cuevas late. I think Cuevas might just have a bit too much firepower for Brown. Brown showed good whiskers and ton of guts against Trice, Blocker and others but I don't know if he can take Cuevas' best.
Cuevas early, or Brown late. I'll probably go with Brown late, but Cuevas stopping him early is not outta the question. Brown had a good chin, but he was no Lamotta or anything, and Cuevas had sick power. But still, if it goes deep, I think Simon would drown him.
I dunno. Basically, if he could hit you, Cuevas WOULD knock you out. It was kinda that simple. There's never been a welterweight banger like him, IMO. I understand plenty of people think Hearns punched harder, but I just don't see it. Brown would be there to land on, but he'd be dangerous with his own left hook. I predict PAIN.
I think X nailed it, it is an either/or type of fight... either Cuevas hammers him into submission early or Brown drowns him late