While I was fitting a thumb safety, reducing the radius of the frame tangs, I began sanding the tangs with long strips of sanding paper. Well, part of these strips were sanding down the top of the rear frame rails with the movement of my hands. So now I have sanded down rails that look off when the 2011 is assembled. What can I do to correct? Can I add material to the top of the rails through welding and then machine to spec dimensions? Or am I stuck with this frame?