When you get to 1/2 inch...."about" is NOT good enough because a true 1/2 inch may be enough. So it would save you a lot of work, time and money if you would get an accurate measurement for us. It also depends a WHOLE lot if the 1/2" is to a nose of a pulley or to a fan blade. If you can fit a 1/2 piece of plywood and still spin, you are in. (1/2" plywood is 15/32).
As Jerry says, no funny business with worn out mounts.
Something seems fishy here, I have done this on 55.2-59 and don't remember that tight, believe you can move motor closer to firewall.
