A friend of mine did his, using mine as a guide. I believe he drilled a pilot hole and then finshed with a dremel. It did not look the best, but once the stock was attached you did not see it. Mine is one of the buffalo length brass framed ones, got it as a gift. It is a tack driver with the stock. I believe you also must get a special hammer screw,the head of the screw is extended and has a nut on the other side. This catches the "hooks" of the stock.
Here is the beast that never was with a few friends
And in his summer home.