Drill the stock oversized full length with a spade bit plus extender. Get a piece of threaded rod the diameter of the bolt . Cut it exactly the length of the stock. Thread it into the receiver and slide stock into place. Make any adjustments to fit of stock. Use a large bit to countersink hole for nut. Add appropriate fender washer and nut. Tighten nut with socket wrench until very tight and cover hole with butt plate. Worked on a cheap import 410 shotgun I had.