My housings look just like your "before" pics.
The finished product is the best I've seen. Do you think spraying the finished product with Eastwood clear coat will prevent fading?
BTW, I couldn't read the stamp on the plate. Mine says "Made in USA". Is that what yours says?
Yes Mine also have MADE IN USA stamping on back.
If your Coloring is similar to my before I would assume they were yello cad, Checking the finish under the white paint will provide you with conclusive plating finish as built.
We had a lot of Fun with this project. I do not protect the plating as it can alter the sheen, I did it once I figure the way I pamper my Cars someone else will have to refinish it years from now.
I noticed that the title reads RS, while these lights are the same R/S equipped or not.