Installing the Magazine Release on an AR-15

First, separate out the parts. Magazine release button, magazine release, and mag release spring.
Insert the magazine release into the receiver.
Flip the receiver over (hold onto the mag release to keep it from falling out) and put the spring on.
Put the magazine release button onto the magazine release.
Lightly thread it on, just to hold it steady.
Identify your buffer detent pin from your lower parts kit.
Line it up with the hole in the center of your mag release button.
Press down enough on the receiver that your mag release sticks out quite a bit.
Rotate the release until you feel that it's about right.
The button should be flush, or just below flush. If your magazine latch is sticking out through the center of your button, repeat the earlier procedure but reverse the direction so that you're loosening the release one turn. You're done.

-- SeanNewton - 16 Jul 2008