My 1980 seat backs don’t have the lower tabs. Was that something year specific? Which upholstery vendor has the best color match for the cream interior?
Tony

Specific for early 1979 perhaps (my car is 3/79)?? They hold the stiff vinyl strip at the bottom of the upholstery back 'flap' and place tension on it.
Interesting that Chris also told me that none of his seat frames had the tabs. Their upholstery just pulls down into place.

Vendors will send color swatches of their vinyl for free, Tony, and you might want to compare with your present upholstery.
I had several sent before making a decision on color,...and I wanted to see the thickness of the color layer, and of the material.

Oh, just one last post on this,...I re-installed the horizontal "wiggly" springs that support the seatback in their original orientation. I removed them for Chris Obert, so that he would have better access for welding.
I'm trying to figure out a way to keep the horizontal rod from cutting into the upper seat foam. My foam is cut clear through at the upper, horizontal list (upholstery wire), because of the rod, and I'll need to deal with that problem, too.
Working on it,...I'll post it in "Re-upholstery" in Restoration Projects.
Best of luck with those seat frames, guys!
Todd.

I got lucky and the passenger's upper seat-frame only needed some minor straightening - and the nuts had broken loose on the adjuster-hinge side (right side of pass. seat),...otherwise fine. Bought some new 13mm bolts, and I'll JB Weld the nuts to the frame in the old holes, using the new bolts to clamp them in place.
I saved all of the old foam strips that padded the sides (and back) of the seats, so I'm reinstalling them. The frames will be 'factory-like' ready for upholstery.
Happy New Year, all! Enjoy, and stay safe!
Todd.