Have an early FN H.Power 9mm s/n 19957,painted black. The internals are in exc to near new condition but the exterior looks as if its travelled around in someones toolbox.I intend to remove whats left of the external finnish,but am surprised at just how strong that finish is. It is ex British army issue so ive been told,so I am wondering would the black spray paint used on car engines do the job,or is there some special paint product that would be needed. Thanks for any assistance.