Just finished my first build, it went really well. Got to check head space and have the muzzle device fixed to really call it complete. I use Aero Precision receivers, and have a couple of tiny spots where the black anodized finish got nicked, mainly on the underside of the forward assist mount location and the end of a few roll pins. I know I won't care about it in a few months, and nobody else ever will, but I'd like it to look pristine for the first range trip. Any suggestions on materials and techniques to touch up those spots?