Tyson takes this one pretty easily.
Norton never could handle moving backwards, nor a hard hitting aggressive puncher....(see Foreman, Shavers, and Cooney fights). While Shaver and Cooney both came past Norton's prime, the fact remains that a skilled or even somewhat skilled heavy punching aggressor always had the edge over Norton's style, which worked better against thinking counterpunching boxers because his style was always so hard to figure out.
Aggressors such as Foreman, Shavers, and Cooney didn't care about his style, they just cared about separating Ken from his senses. Conversely, Norton did well in "chess-match" style fights as he did with Ali and even a younger Holmes (the fight was decided by 1 point). He needed that atmosphere to succeed. Against kayo artists, Kenny didn't have time to think; and he wasn't effective at fighting backwards.
Tyson, who was Mr. Aggressive, (and very, very effective on the attack) would stop Norton in 1 or 2 rounds IMHO.
Tyson by early KO. Norton had trouble with big punchers. He was KOed by Luis Garcia in 8 rounds, by Foreman in two rounds, by Cooney in one round and by Shavers in one round. Tyson started fast and he had fast hands and real power in both hands.
Norton was a good all around fighter, had a very good jab, had the size to trouble Tyson but his chin prevented him from being successful against big punchers. Also Tyson was a fast starter and I just dont see Norton weathering his first three round storm. Shavers, Foreman, Cooney all halted him early. Tyson who was faster hit just as hard as these guys would get him out of there first 3 rounds. Bad style match up for a very good heavyweight in Norton.