Have had experience with other brands of shotguns with glued on recoil pads. The glue used is called hide glue and the pad is best removed with the application of moisture and heat along with gentle prying with a very thin bladed blunt tipped knife. Most times I’ve been able to remove the pad with no damage done to the stock by working the tip off the knife in (between the stock and pad) while holding it over a steaming teapot. By working slowly and introducing the heat and moisture of the steam against the knife blade and into the joint, the pad will come lose.