I believe the tail light housing corrosion repair was discussed in the huge corrosion on new Airstreams thread. As an owner of a late model Airstream, you may find that thread interesting reading. There is lots of tips on how to keep your Airstream looking good and mitigate the "white worm" filliform corrosion.
I believe folks like Corrosion X for protecting the aluminum on these late model Airstreams. I have stripped off the old clear coat on my vintage Airstreams and have to polish and wax yearly. But just addressing the tail light housings would be much easier. I read one Airstreamer was going through the expense of chrome plating the housings.
So for me, I would polish the housing until nice and reflective, and then keep them "waxed".
There is the huge thread I was referring to.