i picked up a mossberg 590 pump from the cop shop not too long ago for 199 plus tax. has a pistol grip stock on it already and i love the thing. the two tone looks really nice. it was a police issue at one time so it has its share of scuffs on the finish. nothing that stands out from a short distance, but enough to notice looking at the gun up close. whats the best way to polish it up and clean some of the scuffs up on it without hurting the finish?