I'm sure others will chime in soon but I'm pretty sure the bolts are supposed to be 18lbs of torque. Any more than that and you might cause some damage.
Here's a link to the Plenum Spacer thread
http://www.camaro5.com/forums/showthread.php?t=216432
and the Insulator thread
http://www.camaro5.com/forums/showthread.php?t=188097
All of the answers should be there...or closeby
I have all three (intake manifold, plenum spacer, insulator) on order and plan on doing a install video/pics and tutorial when they come in