I think at heavyweight the speed and craftiness of Byrd would give Toney fits. As great as he was Toney wasn't exactly twinkle toes out there and could have deliberate flat feet. Now if Byrd comes in like he did late on, where he could fight like he was trying to prove a point and over compensate loading up etc..then he'd give Toney his best shot with up close countering. Byrd also liked his early heavyweights slowish and didn't face many speedsters. Until Ike turned him into a preachy pretzel the worst he had been hurt was to a cruiser Williams who had him down and literally out on his feet saved by the bell. Couldn't have two more diverse personality types either