Upper right corner: Obviously should be slotted, not Phillips. But flat head, or oval?
Oval
Steve, I'm not sure about all years, but at least some of them were nickel plated. I used stainless steel slotted oval head screws, they look nearly identical. Dave
Steve when I restored my 24 Coupe I noticed that the interior screws were nickel plated. I thought that the screws were originally just plain unplated screws but after much head scratching the originals I took out were plated. I had bought a set of plated screws but I wound up cleaning up and carefully polishing the originals.
I am 99% sure the originals were plated as all the screws around the Coupes windshield frame had never been removed. They were just painted over.
All the interior screws were oval slot headed screws. The switch plate included.
Maybe Dave Sonoski or someone who is knowledgeable about interiors would know for sure if all T's or just some of them had nickel plated screws.
Steve, for what it's worth, all the interior screws, including the ones that secured the switch plate in my 25 TT closed cab were slotted, oval brass screws painted black.
It seems logical, then, that the cars would have had nickel plating over the same brass screws...But I could be wrong...
I just talked to a motorcycle restorer last week. He uses one of the small electroplating kits to nickel plate spokes and small screw heads. he just attaches an electode to the screws and dips them in the charged solution.