If you have the chrome recessed Ignition assbly that has the old style GM key. There is a hole beside where the key inserts. You insert the key and use a paperclip to push in and that releases the tumbler. You rotate slightly to pull the key and lock cylinder OUT. Once that happens you can unscrew the outer chrome bezel from the inside ignition assbly. Now, once that happens you will see the quick connect of the ignition harness and you disconnect that. Pay attention to the condition of the spade terminals to make sure they are not burnt or pitted. On both the wire harness feed and the old ignition lock. Doug