Tens of thousands of those transmissions were used behind Chevy V6 engines in S-10 pickups. I'd suggest doing a salvage yard search for a good condition low mileage core before spending much money on a trans that has obvious problems. Any good local trans rebuilder should know a few reliability upgrades he can incorporate during an overhaul.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!