yep, I agree with Dunbar. You can't "crush" the cpu as long as you alternate which screw you tighten per the instructions and you give it a only a few turns each time. The way the stand-offs are designed, they will spin once they bottom-out, so they aren't putting any more pressure on the cpu. The only thing you might want to try is adding another washer per the instructions for AXP's if you don't think the contact is tight enough. I didn't bother, as I was getting great temps on my AXP w/out the need for the extra washers.
Chiz