Amos Johnson, beat Ali at the Pan Am games and Henry Cooper as a professional died recently. I don't know much about him. His name often pops up though as a sparring partner for many of the big name heavies of the 60's and 70's.
As i recall Amos featured on the Front page of a Boxing Illustrated Circa 68 and the Article was about how he was kicked out of the George Chuvalo camp for Giving George a pasting in Sparring...and Flooring him... And the usual about rising to the top of the heavyweight divison, some time later Amos had a chance to raise some eyebrows in a fight with the comebacking Sonny Liston, however he failed to cover himself in glory ..a three round capitulation as i recall, maybe his years sparring with the younger Sonny clouded his desire on this occassion, someone once described him as a poor mans Eddie Machen, i think thats a fair description, perhaps on of those yesteryear fighters who would of done well a few decades down the road in a cruiserweight division.