I'd take a prime Hill by decision to be honest. A clear decision at that. Prime Hill, meaning the late 80s version, was sharper and faster than people remember, and he had sneaky power in his counter hook. I think his piston jab would disrupt Calz's rhythm, and Hill's speed and pop would keep Calz honest. I dont have much confidence in Calz being able to handle an elite level lightheavy.