Ederm:
The firewall etc. on your car would be the correct color. Those early iridescent paints had a very fine and small amount of the "iridescent" material in them. In comparing the later metallics to them, the old colors show up as non metallic. I have had two cars that were Oxblood maroon iridescent and it is very hard to see the metallic, but under the right light and with polishing the paint, it is there. The challenge is to get the paint store to mix the original color correctly with the proper size and amount of metallic, otherwise the car won't look original.
The top bow and the pieces over the doors should have been originally painted tan. If they were painted body color,it was either a special order or was done after the car left the factory. I assume your car is a '39 Cadillac or LaSalle convertible coupe. The Authenticity Manuals have this information.
Terry Wenger