When looking at the back of this Drysdale card, the miscut is on the back and not on the front. One portion of bottom border on the stat box is missing....likely the reason for the MC. The centering on the Williams is apparently in line with the qualities associated with a "5". For a 5, here are PSA's centering requirements: Centering must be 85/15 or better on the front and 90/10 or better on the back.
http://www.ebay.com/itm/1957-Topps-B...item23302b868c