Bobby Chacon was one of my all time favorites. What a warrior. But he was at his best at FW and JLW. He had some good wins at LW, but at that weight he would have been stopped by a prime Beau Jack.
Chacon was at his prime at Feather... and Jack would just be too young and strong for him at Lightweight.... the fight would probably be simular to Chacons bout with Mancini with him being outmusceled by the younger, stronger man....