no need to sandblast them thats a lot of unneccasry work. the oem finish adheres to the aluminum the best so theres no need to strip them if ur plan is to paint them. if u where to have them powder coated they would need sandblasted. if u plan to paint them yourself then you need to make sure that you sand them really good and have them really clean before you apply paint. the previous post has good suggestions for teh paints. you can sand the wheels with a scotchbright (red) and if theres any major nicks that u want to get out you can sand them with 320 first them something finer second, such as 800.