As it would appear that you're new to this, I would recommend that you PUT YOUR DREMEL TOOL AWAY!!! The Dremel is the WORST tool for the beginner's home workshop, as it only seems to help you make mistakes faster. Note that many of the surfaces on your pistol are bead blasted, and restoring that finish is not feasible to do without...bead blasting. You can polish out blemishes with 400 grit paper, but it'll leave shiny spots that likely won't match up with either bead blasting or factory polished/brushed flats. Your best recourse is likely to leave the blemishes alone.