Make a scraper out of a piece of 1/4" steel rod. Bump up the end by tapping it with a hammer. This will create a hook. Now, file away everything of the expanded steel except for one area that will do the cutting. When you run the rod into the hole orient the hook on the side you want to cut away wood - up toward the lock and over toward the centre of the stock. Continue removing wood until the hook doesn't cut anymore, and then bend the rod just a bit about 2" up from the hook. Now the hook will continue to cut. In no time at all, you will move the hole in the direction you want. Now cut away the thin wood around the oops until there's enough to make a decent glue edge, make a plug to fit, glue it in and the rest is easy. After you have finished the stock, stained it and applied finish, you'll be happy with the stock. We've all been here.