Interesting fight and I tend to favor Tyson, because he was faster, a two handed puncher, and, at his peak, a better defensive fighter.
But that is all against taller fighters trying to stay away from him. Somebody mentioned above, and I think it would be prophetic, that Tyson had that terrific uppercut. But here's the thing: it would come down to who controlled the distance. Tyson did his damage on the transition from "out" to "in", whereas Frazier liked to fight inside. If Frazier is uncertain on that transition, Tyson will freeze him and land that uppercut. If Frazier can get inside and stay there he'll win.
But I think tyson would beat him.