Theres no way in holy hell Kenny Norton would've beaten Joe. NONE! Terrible style matchup for Norton. A Frazier left hook would leave him out cold in about 7 rounds.
Joe by KO, and Kenny knew it as Kenny was Joe's sparring partner for a couple of years. Joe knocked him out badly in New York while Kenny was sparring with him for the first Ali fight, and it the session is detailed in Norman Mailer's book-"King of the Hill".