Excellent ambi bolt release but not for the entry level installer - Dark Storm Industries Ambidextrous AR-15 Bolt Catch

Great product, easy to install i used a drumel with a diamond bit as close to size of the channel as I could then cut for the bar. Next the ambi arm made contact with the upper ridges of the humps that go around the mag release and I removed the material around that until the ambi bolt release moved free and easy.
I painted the riffle multi cam si I had to paint the ambi bolt release for install. But hare are some pics hope it helps.
Maybe my mistakes will help you not make them when you install this on yours. It's for sure not recommended for anyone that is not ready or comfortable with cutting into their riffle but if your ok with that skill its pretty straight forward and easy just go slow and take a little at a time .