I'm getting ready to paint my fenders. They are just fenders right now with no screws drilled for attachment to the frame or chassis. Should I go ahead and paint them now or wait until I know how they are going to be attached to the chassis? Is it ok to drill a painted surface or will that require repainting? I'm assuming that I'll prime the surface with something from the Rust Doctor but I'm not sure if there is some other surface preparation that I should do first. The fenders are steel and in nice condition with no paint on them at all. Should I use something different on the underside than I use on the top?
Thanks.
Kris