[carguychris]

Merbeau's post is spot-on.

The only thing I would add is a clear caution note that, in my experience, the magazine springs are NOT symmetrical front-to-back or top-to-bottom. The magazines can be assembled with the spring turned incorrectly, which will result in improper feeding.

The second-to-last paragraph talks about this but doesn't make it entirely clear.

Hint: Put a dab of paint, fingernail polish, or typewriter correction fluid on the front top of the spring before you take it all the way out. This will provide a clear and simple guideline for reinserting it properly.