well guys, it ended up not being the coupler after all. i took all the belts off today, just to double check every thing. to my surprize, the outer ring on the balancer was loose, the rubber elastisimer was broken, ordering a new balancer tomorrow.
for anyone that has a rattle at idle, defintly check the balancer too before you rip the supercharger apart.

the pulley on the crankshaft.it absorbs the harmonics produced by the engine

yes, this little thing does alot. it is the drive pulley for both belts, it absorbs harmonics in the engine, plus it has the interupter on the back side that give you the sync and crank signal.

ok guys. i think that everyone needs to check this out.
i replaced my balancer today. the entire rubber was broken out. GM has redesigned the replacement balancer. the rubber is no where near as wide as the old one , giving it more stablilty. it wont fly off when it breaks the rubber. i would have to say that is was going for some time. this also could have been some of the knock retard i was getting too. then when it wore enough of the rubber out, then it rattled, also moving the balance point too. i got the balancer for 129 bux. the old balancer, the rubber ring was aprox 1" thick. the new one is maybe 3/16-1/4" thick. almost like a small block chev. balancer.
if you have time and a series 1 motor, please check your balancer. the local part store i go too for speed parts, the guy that owns it has a 2002 impala, fully decked out. he has other 3.8 cars too. he told me tonight that he has had like 5 cars that he had to replace the balancer on due to this.

we have a dealer deliver to us 2 times a day at the shop. they changed the part number and redesigned it too. also the old number listed for 217.63. the new number lists for like 155.00. our cost at work was 129.00 , so my boss sold it to me at cost

also, are you still looking for a 92-93 TB. i have one sitting here if you wanna make me an offer