Without looking at my car seems like they are held in with a couple of screws. Look at yours it should not be too hard to figure out.
IIRC the two tails themselves are replaceable as well as the springs behind them. I think you push the tail into the body, and slip the outer end past the little retainer tab on the edge of the V opening. There might be somebody reproing the inner housing that rivets to the backside of the door jamb, but I've never seen one.
alchemy is correct on replacement of the dovetail and spring. If you need a replacement "metal pocket" in addition to the dovetails and springs they used to be available through C and G Early Ford Parts, Escondido, CA.
metal pocket & dovetails need to be replaced well guys mine are riveted & spot welded to the door jam it was fun & there are out now!!!!!!!! BOB
You might give **** Spadaro a call, he is a regular here and has lots of 40ish Ford stuff, all high quality. I'm sure he is an alliance vendor, check thier index for a number.