Rear seatback R&R HELP!

I need to find a replacement rear seatback for my 1996 Caprice wagon.  Are all of the 1991-1996 Caprice backs interchangable?  How about those from Roadmaster wagons?  The cover of the seatback is easy to remove and swap.  But which ones will fit the existing latching mechanism in a 1996?

I have access to a number of hulks at a local scrapyard.  Is there any trick to removing a seatback without damage?  Of course, mine pops right out very easily, but that's because the area of the seatback around the pivot pin on the passenger side is trashed. What's the proper way if the mechanism is intact?

DERP!  I found this in a post on this very forum from 2009:

"Pull the carpet pieces apart where the velcro attaches the cargo piece to the seatback (roll the piece onto itself for ease). On the passenger side hinge, you have to slide a flat nose screw driver onto the hinge rod, and slide it into the seat body. It's spring loaded, and keeps the seat hinge rods in their place. Surprisingly simple..."

Of course, I still would like to know which seatbacks I could swap, assuming I can get the cover to fit.

94-96 only. The mounting system for the 91-93 cars is completely different. Roadmaster and Caprice interchange.

The post that sticks into the locking mechanism is the weak point. Make sure any seat back you are considering has a solid post.