No suggestions just advice
If you detail strip it you will find a hook shaped sear on a bar be very carful how you insert and reassembal this piece it will fit backwards andWILL NOT COME BACK APART
the gun will completely reassembal and function but will not field strip again
To take it apart you must drill a hole and lift the hook with a pin
i don't have one available to look at righ tnow, but shotgun news has someone in the classified section that advertises what you are looking for.