Well let's see now. The locking bolt on these Stevens guns is wedge shaped engaging the slot in the rib extension from the left. The lower surface has the wedge to compensate for wear so as the actual bolting surface wears the lever comes further around to take it up. By peening down the top portion of the rib the bolt is hindered from going as far & while it has improved the "Cosmetics" of the gun the bbls are actually not being drawn down as far into the frame, as this is determined by the "Lower" part of the extension. I will take good note of this & not get either of you to work on a gun of mine.