Thank you for your response! I was at a small car show and again, was studying hardware
. Only one car had factory unpainted bolts, and they were phosphate and oil. I like that look, so I'm glad to go with the phosphate finish.
just about all my hardware is original, with most of the bolt heads having the 'SEMS' stamp. I have a few with circles and the larger ⅜" with "26" on the head.
I wish when I had started this restoration 20+ years ago (I had a long hiatus), that I would have made more explicit notes on the hardware (digital cameras make restoration SO nice!). Oh well, at least I'm reconditioning it all and putting it back on the car with ~90% accuracy