Warning If there is any chance the paint on your mirror was produced before 1978, it must be tested for the presence of lead before any stripping or scraping can take place. Do not use metal scrapers on a mirror, as they can easily scratch the surface. Unlike ordinary dirt or grease mar...
We sell 3M Scotch Brite's Paint and Rust Stripper Kit, a paint removal disc that securely attaches to your drill to make a makeshift sander for wood, metal, and plastic.
Avoid epoxy when there is strong exposure to light as it doesn't have good UV resistance. Other than that, if you are painting paint rather than painting bare aluminum, any paint made for metal will probably be fine. If you are painting bare aluminum, see the previous responses. Good luck...