Hi Dan,
I am in the slow process of polishing the outside of my 24' Landyacht Airstream. I bought a gallon of Met-all directly from Airstream. I use my Craftsman buffer and polish a little at a time. I've gone through 6 buffer cloths, you have to keep washing them out. It is a very big chore, don't let anyone kid you. In 2 years I have half the streamer done-one side only. But it looks wonderfully shiny new !!!! which makes it all worth while. And a big plus is I'm saving thousands of dollars. Good luck to you if you a planning to do it yourself. Keep in touch!
Janet J. Woodbury, MN