That's why I was so sure and skeptical. My manufacturing training told me no one would paint screws and keep them in a bin to get chipped. Handle them, screw them on and get chipped, touch them up.
I realize now that maybe back then it was not seen as a big deal to touch up. They did not refine mfg techniques. Cost cutting was not in the mix yet. Sales, beating the competition and quality was. I figure they didn't want the carbon steel hardware to rust? Craftsmen don't build/paint cars now, assemblers and robots do.
Today it's black anodize or stainless steel or plastic caps covering screws.....or snap on trim with push on's.
I have to admit, I have painted some hardware during an old truck build. Mostly motor stuff.
