90q squeak squeak?

[Andrei Kogan <abk@phy.duke.edu>]

My next step in our never-ending journey towards making our 88 90q feel
like a brand new car is  to fight the cabin noises. I have id'd at least
three distinct squeaks, annoying as hell:

1. Front seats. Both show some play in the backrest, and both make squeaky
noises. I seem to remember a discussion about seat restoration a while ago,
but that was for a 100/200 cars. The suggested cure was to replace teflon
(?) bushings in the seat assembly. If anyone has any specific information,
part numbers etc please drop me a line.

2. The passenger's seat belt lock. The inside plastic pieces start rattling
like crazy at certain rpm. Sounds like the floor is about to crack open.
Not sure what's wrong with it.

3. The trickiest of all: There is *something* loose in the passenger side
area behind the back seat. I previously thought it was the middle muffler,
but I don't think so anymore. That muffler does have a bit of noise to it (
probably a loose internal baffle ) but it is only sensitive to rpm.  The
SQUEAK  mostly happens when going over bumps, and it appears to be coming
from inside the car , it's too loud to believe it's either in the
suspension or in something else outside. The shocks were out of the car a
month ago and I was told that the upper mounts were OK.

I have never looked at the area behind the passenger seat. My only guess is
that  the fuel tank is somewhat loose. What else is in there? I  made sure
it's not something in the trunk -- emptied it, drove a little -- same thing.

Please let me know if any of you have had a similar noise.

Thanks,
Andrei