I have a 95 GSR with Comptech catback exhaust, I have a really bad vibration coming from underneath and it only vibrates right at 2500 rpms and up. I was wondering which heat shield it might be? I've already checked the one around the cat, and it's tight. Should I just remove all the other heat shields located above the exhaust piping? I mean those heat shields don't seem to do much anyways, the metal is so thin.