[OT] Diesel Rabbit clutch q's

[doubt at inwave.com (Nate Mellom)]

A friend of mine has an '82 Rabbit L diesel, and the clutch is toast. 
 From what I've been able to find online, there were 2 clutch options in 
'82, a 7 7/8" and a 8 1/4".  Is there anyway of telling which one this 
car has without a teardown?  Does it really matter which I get, so long 
as it's a matched set (pressure plate/disk/etc)?

Peter, you got me a good deal on the radiator for this car, and the 
owner is still on a tight budget.  Any chance you have any deals for me?

Thanks!
Nate