I know it's wrong that I have to ask this... but I have no idea how to take apart a 1911 magazine.
Can anybody give me the quick how-to?
Depress the follower below the first couple of witness holes, put a pin or pick or something that will fit through the holes below the follower to trap the spring. shake the follower out being careful to mind how it goes back in. Point the magazine directly down on the table/bench and remove the pin to relieve the tension on the spring, again, being mindful of the direction the spring goes in.
Seriously, do take note of how the spring is in there and in relation to the follower. If you put it in backwards, the follower will want to move too far forward on the last round. Really, it's a piece of cake.
Hacksaw'll cut off the floorplate (hey - it's now a "removable" floorplate!), duct tape puts it all back together.
Hacksaw and duct tape, and when in doubt, use a bigger hammer...
If you use a grinding wheel on the seams you can reweld when clean.
Pliers have been used on both ends with mixed results. Straightening the feed lips is slightly better than pulling of the baseplate.
Pliers should not be used to tightly grip the mag while working, and if you must put it in a vise care should be used.