1966 Speaker Cover Color

[Cavalry]

After a long hiatus I am back! I recently acquired a 66 U15 as a parts truck. The louvered radio cover was a new one for me, I haven't seen one before in the 40+ broncos I have had. Its red with rust compared to the dash which is in not terrible shape. Thinking it was just poor factory paint I popped it off to look behind, and was surprised to find the back was still in perfect shape but what appears to be red oxide.
I can only assume it was suppose to be the dash grey color from the factory but the red oxide is strange. Were these grey both sides, grey on the front only, all red oxide, or someone along the line just put a primed on on there and left it?

 

[okie4570]

Red oxide was what the entire 66' was primered in. The cover should be bronco gray poly just like the dash. Usually they were only found on u13's, cool find though.