Pontiac Firebird 1967-2002 - 93 Trans Am Electrical Issues---NEED HELP!!!

My mechanic cannot figure out the problems with my 93 T/A 350 LT1. When the motor starts, all kinds of crazy codes pop up:confused: (airbags have deployed when they haven't, oil temp is -36, etc.) As soon as I have a chance to find out what else is up, I will post it. He has been trying to figure this out for quite sometime to no avail. Car has 72,000 original. I'm considering purchasing a 400 ci block from B&R Racing here in Pittsburgh 475HP for $2500 (I called another place that had a stock rebuild for $2299 w/ a 4 year warranty). Should I do that, my 350 will be up for sale. Anyone have any idea what a good 350 with low miles is worth? Thanks guy. Any techs or mechanics with any info would be greatly appreciated. Any way to tell which rear end I have?

I heard that gu2 means 2.73 gears and gu3 means 3.23 gears. I think the sticker is on the door jam.

Appreciated and any idea on the electrical side?

Should really list as many of the codes as you can because it helps kinda narrow it down, but personally when I have an issue like that the first think I do is check all fuses and relays. The next thing that it could be is a ground is loose or has come off. It could be a bad wire in the harness or even a bad BCM(I think the 93s had them but havent worked on LT cars alot). Unfortunately the best thing to do maybe to pull the body harness out and check it all out.