For the DW and the Colt, do this:
1) with a NON-marring implement (like a plastic ball-point pin cap, q-tip, etc), push in the exposed tip of the firing pin at the rear of the slide.
2) with the fp depressed, slide the firing pin stop (the square steel piece you just stuck the improvised tool into) down and out. Keep a palm cupped over the rear of the slide to prevent the firing pin ejecting out and into some random corner, the cat, or your lawn.
2.5) Colt Defender only: depress firing pin plunger into slide to release the firing pin.
3) remove firing pin and spring.
Now, two more things:
1) Your extractor is now unsecured, and may fall out if loose in it's tunnel. Don't loose it.
2) On the defender, you also have the firing pin safety to deal with. It will be retained by the extractor, but if you let the extractor fall out or remove it, the plunger and spring will come out, too. Don't loose them.
3) DON"T use a paper clip, small screwdriver, etc. You will slip at some point and scratch the frame.
Don't know much about CZ's.
