I just purchased a used Stihl BR420C magnum. it was a basket case machine that was all torn down but it looked almost new. it looked like it had a blown cylinder gasket. The only thing I am not sure about is at the very bottom of the cylinder sleeve on the manifold side and not quite in the center it looks like a small chip of the nickle plate finish some how came off. the surface is still smooth where the finish is gone. the nickle plate that is missing is about the size of a bb for a gun maybe alittle bigger. is there anything that can be done to fix the finish that is missing. would it still be safe to run it the way it is or would the rings get caught on it.