I have two different styles of the seat back latch knob -- one pair which I believe came from my SJ March car and one from a parts car. I have two of the long style and only one of the short. I think the two long styles came from the Shelby.
They are listed in the NPD catalog as long and short style. They are both chrome, have a Phillips head and 1/4-20 thread. I wonder if this is a running change, a vendor for SJ only or something else.