Rockauto.com has recently started listing parts for the earlier Isuzu diesels; you might try them.

Also, check sunburybrakes for clutch parts. I bought a 4JB1-T kit from them which is working well, supposed to be a bit heavier-duty and cost about the same as the rockauto kit when shipping is included. The kit didn't include the pilot bearing, but I found that it's the same as the gas engine version and thus easily obtained. Perhaps the same goes for your engine?

Last edited by acy76; 01/03/10 12:57 AM.
1988 Isuzu Trooper LS
2.8l Isuzu 4JB1-TC intercooled turbo diesel
www.dieseltrooper.blogspot.com