If it's like most synthetic stocks the reinforced area for the recoil pad screws runs the length of the inside of stock. Measure the pad screw and drill a hole a 1/4" ahead of screw length. Drill the hole slightly smaller than the sling screw and slowly screw it in the sling screw will thread the plastic stock and the sling screw will be tight and not back out. In the second picture you can see the sling screw next to the white dot. This was a 870 stock that was shortened 1" and the pad and sling swivel reinstalled