My "new" '86 'Burb was grinding as it cranked since I bought it on Tuesday. So I looked underneath and the inner starter mounting bolt was broken. Got the piece out, removed and opened unit, looks good. All bushings little wear, drive (one way clutch) tight, etc... Put it back on, with strap (wasn't on before), and still "clashing" as it cranks. Put a thick shim on, and sounded the same. But now the drive stuck against the flywheel, and had to panic to disconnect the batts! Put two thick shims, same disaster. I used a Taiwan solenoid, didn't forget the return spring(!). Could the nose be machined out of alignment? The flywheel looked alright, considering the grinding I put it through. I've re-built my own starters for 25 years, and find it odd that I used two shims and there were none originally. Sounds like a different problem. I recall reading the GM shop manual about the shim issue, so I know a little about the issue. Oh yeah, flywheel had a "ring", even though it was (of course) still bolted to the TC. This starter had been on for a long time, as the cable nut was badly corroded. Might have been the original, had the sealer between the nose and solenoid. Should I open my wallet and use the gear reduc. unit from '91>. Ebay $150 new http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7970070323&fromMakeTrack=true, locally $250 reman.