Jeff,
Thanks very much for taking the time to find these additional photos. It is hard to find clear photos of this area and I had not been able to find any good examples from unrestored cars.
My car was originally "restored" around '89 in northern California and most of it was detailed like a San Jose car, these screws being one exception. Based on your evidence below, I think I will follow Charles' lead and leave them all in during the repaint. Easier to change later if needed as more data becomes available.