I don't think those things are of any real use, unless
you keep it in your car and use it as a club to beat
people away from your super flash sled.

I'd use B30 engine mounts and otherwise try to figure
out why the motor is shaking around so much. I've never
seen a B20 that shakes so much that I'd want to use one
and I'd suspect that if the motor's shaking around that
much it would probably rip the sheet metal it's attached
to on the fender side of things.
chris