Cleveland Williams turned pro in a much weaker era. Earnie Shavers turned pro in a much better era. Williams was extremely crude and slow. Shavers wasn't the most skilled guy but he was more skilled than Williams. Shavers also was a bigger puncher. Neither Shavers or Williams had the best of chins. In any case I would favor Shavers to stop Williams early.
I'm going with Big shock early ko.. From Williams. By early im talking 1 round. Williams catching Earnie straight off the block and throwing everything at him! Shavers goes down like a ton of bricks, gets back up and immediately gets dropped again. Williams by ko 1.
Cleveland Williams fought the best in his respective era, Sonny Liston, twice, Eddie Machen, and Ernie Terrell. Earnie Shavers was kayoed in the 1st round by Jerry Quarry, on Dec 14 1973, in Madison Square Garden, but a very deadly puncher. Shavers biggest weakness is his stamina, if he cannot kayo his adversary right away. Big Cat on the floor early, drags Earnie into the later rounds, to score a kayo in round 9. Remember Williams broke Sonny Liston's nose, in 1959, before being a knockout victim to The Bear.