Don't know what you guys will think of this but I tried out the method of dropping pennies behind my trem-block to wedge it solid.

Works great! I gently tapped them down with the plastic handle-end of my screwdriver. I put a couple in the front corners so that the block wouldn't move forward while I tamped them in. It's completely solid.

It took about 5 minutes and cost about 50 cents. And, of course, I can always pull them out with a pair of pliers.

D-Ops