I have called a couple places, got no answer told to leave message and never get a call back tried that twice with 2 diff places then got in touch with 2 other places and they didnt have test vehicles and didnt sound that confident Ive looked online and came up short any one have a good one for a 91 LS

 

ive never heard of repairing an ecu, afaik you just replace them,
you might have better luck in the local forums