Who is the best heavyweight champ in their prime that Leon Spinks could have beaten?

In any interview I've ever seen of Mike Weaver he always seemed like a humble, quiet type of a guy. I remember when I first got into boxing back in the early 80's reading articles in the boxing mags that he preferred playing the piano rather than punching other guys in the face. Maybe that's why he disliked the nickname. Certainly fitting with his physique, and coming from a guy that had Norton's build that is a compliment. He also said that despite having a 6-6 record it was Norton who saw that he had a lot of potential and could be a force to be reckoned with if he took boxing more seriously.
Interesting also is that they both were California fighter's, with bodybuilder-type bodies, and they both served in the Marines.

 

Seldon

 

Leon Spinks Olympic Gold medallist, World Heavyweight Champion who beat the man who beat the man.
I would settle for having that on my CV.
Could he have beaten other prime Heavyweight Champions, i think the list would be limited if it the Leon we saw. But if he had the right team to have developed him, kept him focused, kept him from his 'bad ways' outside the ring, then maybe would have stood better chance, but alas we will never know.
Pity Leons time at the top was a for one night only episode, but that one night in 78 put him in the annals of boxing history for ever.
Good to see him this week inducted into the Marine Corp Boxing Hall of Fame.