I have seen a couple posts where people have drilled a rail into the bottom of their amd to mount a magpul afg. I purchased a mi handguard rail that is 4 inches long but the bump that keeps the original forgrip from rotating prevents the rail from lying flat. How could I remove or flatten this bump. I have tried hammering it flat with a piece of wood inside the handguard but that has not worked (maybe I'm not hammering hard enough but I dont want to mess up the handguard). Any advice and pics are appreciated. Thanks.

See the thread 'AMD 3-Rail Hand Guard'

Pics of bump? I don't recall having any problems installing a MI rail on mine, other than the cleaning rod getting in the way a little. Also, be sure to locktite it from the beginning.