When screwed down the rear sight blade kicks to the left and the pinned front kicks right. Also, the left side of the sight blade is lower than the right side. At present, I have placed a thin plastic shim under and to the left ( 'L' shaped)just in front of the sight blade. My back up plan is to shim with either copper wire or lead. Is there a better permanent solution? To date, I have avoided pushing out the roll pin.