If you decide to go with a more positive mounting sight , don't overlook the Tru Glo magnum gobble stopper PRO Series. I have a set on a BPS and a set on a 935 Mossy...they use two allen screws on each side to "clamp" into the side of the rib...if you have a vent rib gun.
I really like mine and they offer windage and elevation adjustment.