15 Rounder Personally, even as good as Nunn was i don't see him coping with the underrated power and awkwardness of Turpin, it would be a very competitive fight til Turpin lands one of his hooks and it all goes downhill from there. Turpin by stoppage in the 10th or later.
Turpin has a chance if he can get into mid range, he threw some unorthodox punches and Nunn had his hands down and could be timed.
Nunn was very good in his day, up until Toney many were calling him the next Sugar Ray Leonard. I think he'd beat Turpin, probably over the distance, he'd find a way.
the Bigger Man... truth is it'd be a S-MW cum L-HW fighting a L-HW cum HW. plus Nunn was a better boxer too. the old adage is 'usually' the case when Smaller meets Bigger.
I think Nunn wins fairly easily. Before Nunn lost to Toney, he beat Frank Tate, Juan Roldan, Kalambay, Barkley, Starling and Curry all in a row. That's six world champion, high level opponents all with very different styles. That is not easy to do. Nunn was a phenomenal fighter.