Red interiors are awesome. You can replace the covers and the foam fairly easily and the parts are available as long as the seats function properly. Simple tools and a straight forward repair.
The column air bag, column, are not interchangeable. The 96 has no passenger air bag either. Check what size wheels are on the donor. If it is 2wd, usually it has 15" wheels, which some of the front end parts would not interchange. 1996 is one year only for many parts.
A self tapper will just vibrate and walk out. Buy a nut cert kit. Drill the correct size hole for the cert, you will install a threaded insert with the tool, and can install a bolt to do the repair CORRECTLY !!!!
The new foam is far superior than anything you have that is 25 years old. Secondly I replaced the seat bottom in my 1999 k2500 suburban, gray cloth, and it matched 99% exact and that is all you can hope for. Again the material and the construction is way better than the stuff 25 years ago...