<VV> clutch question...

[Cash Case]

One more question guys.
Clutch has been in a box for about 8 years. while looking through the  
box to make sure I didn't missing  anything, I found a small o-ring.  
It looks to be about 1/2" in size. Is this a part that needs to be  
replaced that's part of the clutch pressure plate system. I've  
already replace the seal and the thick washer inside the end of the  
snout in the diff. Any know if this o-ring just fell into the box or  
does it go somewhere important?
-Thanks-
-Cash