Both in their prime, who would win?

Chris Byrd was a great defensive fighter,
but he fought slower guys in a slow division.
He was good at making people miss though and had a nice chin.
Record: W39 (20 ko's), L3, D1. Notable wins: Evander Holyfield, David Tua,
Vitali Klitschko.

Floyd had a quick leeping hook, Patterson had quick reflexes and was offensively gifted. He was small and had a weak chin. Youngest Heavyweight champion at the time.
Record: W55 (40 ko's), L8, D1. Notable wins: Henry Cooper, Archie Moore and
Ingemar Johansson.

I see this fight as either split division for Chris Byrd or KO for Floyd Patterson.

What are the forum's thoughts I wonder?