So I recently bought the CDI bottom metal and from what I heard is that you have to mill down part of the receiver to get the bottom metal to fit and allow the magazine to seat properly. My question is with this bottom metal I just bought, I installed it on my SPR. Loaded a mag and wanted to see how much of a gap there was and how much of the receiver would need to be fitted to allow this bottom metal to work. Well the mag was inserted and the rounds would be picked up out of the mag and cycled. The receiver screws also were tightened down. My question is this, if the rifle is able to cycle the rounds from the magazine will my receiver still need to be fitted to work with this bottom metal because at this moment it doesn't seem like it will need to. Is anyone running this system right now that could give me some feedback?