According to the Chilton Corsica/Beretta 1988-1996 Manual, there are 21 steps to removing the ignition cylinder (and another 15 - 20 to reinstall it). Not that I don't want to past them all here, but you should get a manual... they're handy to have for any repairs.
Go to autozone.com they have this information on their website.
Remove the retaining ring at the top of your Chevy S 10 ignition lock cylinder. Slide the ignition lock cylinder out. Remove the wiring harness from the back of the ignition lock cylinder. Reverse the process to install the new ignition lock cylinder.
You will need to remove the retaining ring from the top of your 1975 Chevrolet pickup truck ignition cylinder. Slide the ignition cylinder out and remove the wiring harness. Reverse the process to install the new ignition cylinder.
Remove the retaining ring from the top of your 1997 Chevrolet 1500 ignition cylinder. Slide the ignition cylinder out and remove the wiring harness.
You can remove the 2000 Chevrolet Astro Van the ignition switch cylinder by removing the retaining ring. The retaining ring will need to be turned to the left. The ignition switch cylinder will slide out.
this site will help
Turn it, then pull up and out.
very carefully
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Without the key you are going to have to drill it out.
you can use the car blank key to open it.
I broke my key in the ignition and cant get it out. My only option I can see, is to replace to tumbler. How do I remove it?