I have a custom cut aluminum fan grill that I need to sand nice and polished to get rid of some inperfections and denting and to make it smooth for anodizing. How should I do it? Wet sand with gradual increased grades? Tape down the sandpaper on a flat surface and move the grill over the paper? Or use a sanding block block on the grill? What about the parts that I can't get to with a sanding block, like the small inside parts that were custom cut?