Have used Acra-Glas to attach a bunch of pads WITHOUT screws on various synthetic stocks, and never had any come loose. Among them was the Banser stock on the .338 Winchester I hunted with a BUNCH during the 1990s on hunts in the U.S., Canada and Africa, including horseback pack-trips.
But if installing one on hollow, injection-molded stocks that are shortened so much the original pad screw-holes are eliminated, would probably add something inside such as wood, or whatever works.
