I picked up a garand at an auction last night. Looked to be in pretty good shape. The metal needs some cleaning up, but that was about It. Only when I started taking it apart today did I realize the top of the screw through the windage knob was broken off. I tried boring it with a small easy-out, but couldn't get it. Is there a way to remove the sight assembly without removing that screw? Or am I pretty much screwed? No pun intended.