This 1961 piece in Sports Illustrated remains one of the best Liston stories. I encourage all the Liston freaks on the forum to read (or re-read) it and comment. https://vault.si.com/vault/1961/07/17/cant-a-fellow-make-a-mistake
The story gives a glimpse into Liston's character and how it was viewed by sportswriters of the day. There's also a look at George Katz, the Philadelphia boxing manager, who provided cover to Liston by serving as "manager of record" until the Nilon brothers replaced him within a year. No matter who managed him, Sonny remained boss of his camp.
Thanks so much for this. One of my favourite fighters and the article confirms a lot of what I'd thought.