Hey guys, quick question... I bought some stripped lowers recently, and I want to build a 300 blk pistol. Do I need to register the lower as a pistol lower? Have it engraved etc? I already know the rules as far as buffer tube, stock, vfg, etc. I just don't want to be illegal even if I do build the ar pistol correctly. I am unsure about how I go from here.thanks guys!