Hey guys... Another question for all you experts... I bought a g21 off of my father in law.... Has after market grips and a green slide... Other than that looks just like my 4th gen g17... Anyone know what gen it might be?? Also, the guns in good excellent shape... But the green paint on the slide is wearing in a bunch of spots... Any tips for a do it yourselfer to fix this?? Can I strip it?? Do I have to get it re blued?? Is this job more than a novice can handle and I should take it to a gun smith??