This pic makes me believe that a LOT of internet pics of both are severely morphed.
The first pic in this thread is from the 79 Olympia. Zane's best ever shape. The laughing pic next to Arnold is from the 80 Olympia where Zane lost something like 10 or 15 lbs prior to the show because of an injury. He was thinking about pulling out of the show but Arnold convinced him to compete.
Zane looked like living sculpture.....no one today does,unless you are talking abstract art.......so you do the math.