68 SS - 396 still running the distributor with points. The problem started that the engine kept running (sometimes) after I turned the car off. Then the battery went dead and it showed a drain on the battery when wiggling the key. I replaced the ignition switch thinking that was the problem. Now the car will not shut off at all. Does this sound like the key lock should be replaced now or should I be looking at something else?

Have you replaced anything else like the starter maybe ... Are you attempting to use a remote solenoid or something ? What color wires are attached to the coil? What color wires attached to the starter? If you replaced the switch, and it is hooked up correctly, then I re-check all "hot" wires in your ignition system.

68 SS - 396 still running the distributor with points.
First determine what is keeping the car running. Next time you turn key off and it still runs, pull coil wire (be careful) There are 2 wires at the coil+ . One comes from the IGN switch, the other comes from the starter "R" terminal. Disconnect them and with a test light or meter see which one has power. This will tell you at least where the problem is.

thanks I will give that a try

with the old ignition switch it - sometimes it would shut off and other times it would not - that led me to believe it was the ignition switch.

I will try the test.