I cleaned each lens with soap & water twice, then masked and painted the lens interior using rattle-can metallic paint. One side has definitely turned out better than the other side, but both are acceptable. I won't be showing off the interior of the housing, so who cares if I got a run or two?
One side painted with rattle-can metallic paint. Should be good enough.
The next step of this restoration process is to investigate new connectors. The old connectors are fine for a car that won't see much but sunshine, but I gave up on and sold the original wiring harness. Maybe the choice of connectors will be another blog post.
That's it for now...