So, the rear passenger side seat back in my '92 740 wagon takes a lot of jimmying to get back into the upright position. I figured out there is a part where it connects into the car that is broken. After being unable to figure out what the part was that was missing, I got a hold of another seat back and well... it was broken on it too, but it still had the whole part, even if it wasn't intact. I can't seem to figure out which part this is on any diagrams so I can't figure out a part number to even search for. I'm sure it's discontinued.

 

I doubt you can find that part new but used shouldn't be hard, I threw away the whole seat a few months ago. Most junked 740/760 wagons should have the part in tact although you'd probably have to buy the whole seatback. The problem is few sellers want to b bothered with such small items, there is no $ in it. Try Voluparts.

 

I have the exact same problem you do, please let us know if you happen to find a source for the part.