So I think we will try to build a wooden seat frame for our '34 p/u. We don't have any of the original seat, the cab is channeled and we plan to probably do a mild chop as well (we will see after we get a seat in it). As such, this seat is going to have to be pretty short. Is there any "architectural standard as to what the angle of the seat back should be, what the seat bottom angle should be, how much higher the front (under your thighs) should be as opposed to where your bottom sits? I know alot of this will probably come down to "what feels right" but am hoping to get some dimensions to get us close to start with. Thanks-
I would find a modern car you can fit in, and find a comfortable angle. Make a cardboard template of that angle. Try to replicate that with some foam and plywood in the 34 to mock things up. Stack up blocks to try different heights and angles and see what works best for you. If you can build your own frame and pads the sky is the limit for adjusting to your comfort. Or you could go find a minivan third seat with the right width and plop that in there. They are cheap and might be a good place to start as well.
Unless you are 4' tall, a mini van seat isn't going to work in a channeled 34 cab....let alone a chopped and channeled one!