Interesting - I never knew that North American 60s came with this option - seems it was only in the first year of production.
I have two sets of Asian market (right handed) bench seats - one came from factory with fixed brackets (no recline function), and one with reclining brackets.
I would really appreciate a picture of the inside (parking brake lever side) hinge of both your front seats. The EPC is suggesting that there is a common bracket with my fixed seats, so I would like to see if that is correct.
The fixed seats have (or rather had; the PO chopped them up) single piece brackets on the door sides of the seats, but for some reason the parking brake side of both seats had a hinge running on a nylon bush, though on the passenger (left) side reclining seat, the inner hinge is a larger assembly with a peened metal pivot (that is worn badly, unlike the easily replaceable nylon bush option on the other side. I'm struggling to make sense of it.
Hope you don't mind the odd request!
Thanks
EO