I could remember long time ago Chavez Sr. called out Terry "the Terribly" Norris to fight him at 147 but the fight didn't happen. At that time, Terry was the World Champion at 154 and Chavez Sr. was the World Champion at 140, and both World Champions were at their prime. If the fight took place at that weight, who do you think would win the fight?
IMO if Chavez can survive the first 6 rounds then Norris would have serious troubles in the second half of the fight.
Norris too BIG, Chavez was not "Chavez" @ 147lbs. That said... A well placed Hook could knock out Norris. (Dude had a chin made of paper mâché)