if you intend on doing the stock modifications yourself make sure that you do not remove to much material. this will help guide the mag to the action. the mag should rest between the trigger and the recoil lug with little room for play but if you remove to much of the stock it will strike the trigger or recoil lug on the way up. because I used so many different magazine designs before deciding to use the Wyatt mag need to go back and rebed my stock.
you also need to do some stock modifications to allow the mag to fit through the mag box area. or at least you need to on the shorter rounds. you may not need to on your 460, that's a big round and probably has a big box area to match.