Were early 4 speeds painted?

I bought it the way it is shown in the picture. As you can see, there is black in the pores of the casting, so I think that is just a natural color of the cast, and yes, this is a California transmission, no rust on it. I personally haven't done anything to it but clean the exterior with a light solvent, and avoided the 4 mark. I've read that there are 3 digits stenciled on 4 speeds that tie it to a to the broadcast sheet, but thought that was for later 4 speeds. This one appears to be an early '65 unit built 10-9-1964 per the casting number.