if the mounts are already in, and you dont feel like R/R'ing them, get some big old washers and use a grinder to cut a "V" chunk out of them, so they can slide in around the bolt shank. then bolt them in. shouldnt go anywhere.
how about using something like a chunk of a plastic cutting board. i know these are used to fix broken mounts on eclipses and work well. it should hold up and is nice and blunt. cut them to the right size, cut a channel in it for it to slide in, with the bolt goin in the channel you cut. might work nicer than a washer if you need a little more lift.
just an idea. good luck.