The airbag light came on a few years ago and we found that these are known for having the airbag module under the passenger seat corrode and fail.

I believe this is what happened, since the module was all corroded.

So I went to a salvage yard and found a Monte with no body damage with the same model # airbag control module.

I put it in and the light is still on.

1) does it need to be reprogrammed?
2) the dealership tells me they discontinued parts for this vehicle and can no longer get the airbag module

 

The air bag light is on because a a code was thrown with that system. Odds are you may need a GM Tech II (which a dealership would have) to read the code and then clear it (to see if it pops back up). Not sure what other scan tools might read air bag codes.