What color is a stock 51 3100 heater box?

[Jack Guzman]

I got the heater out of my truck today. Former owner had the heater core bypassed. No idea why. It was in Arizona. The core holds water and appears to be undamaged. When I pick up my recored radiator I'll have it pressure checked.I live in Maine,I need a heater.
Meanwhile I'll be cleaning and painting the heater box.Wondering what color to use. The interior of the cab will be gray.Should I match that or gloss black or --What color was it when built? It is partly colored gold.
I hope you folks don't mind me posting all these questions. I don't know much about this stuff and I want to know it all.(At least all about my truck)---thanks---Jack