I have a new Mossberg 835 camo turkey model and I have installed a Knoxx (blackhawk) recoil reducing stock and wanted to add the Knoxx forearm. I know I need the Houge forearm nut, but it looks like the OEM forearm is pinned to the action bars? How do I remove the forearm? The pin ain't coming out or at least I haven't been able to move it yet.