I don't like the style matchup for Frazier. From Oscar to Muhammad to George, Frazier showed a tendency to get hurt early on. Who starts faster than Tyson?
Tyson and Frazier, like a lot of aggressive shorter fighters, were fairly vulnerable to uppercuts. That favors Tyson, he had one of the best uppercuts ever. Frazier had a decent uppercut but was obviously more of a hooker, especially with the left.
Frazier was more difficult to discourage and was mentally tougher than Mike, but I don't think it gets that far. Tyson likely gets him outta there early.