FYI:
I have had one hell of a search to find a car seat for my '76 TA.
I don't want to put my girl in the front but could not find a non-shoulder harness lap belt car seat.
I purchased a E-Z-ON 86Y Universal Harness. You install the teather and use the lap belt.
Check it out:
http://www.ezonpro.com/products/familyVehicle/86yHarness.shtmlI found out you will need to mount it behind the speaker but doesn't rally interfear.
I will try it out on the kid this week.
Jeff