ignition?

My car the other day didnt want to turn off. the ignition key cylinder just went round and round, so i had to kill it with the clutch. then the power stayed on and am not able to turn it off, so i disconnected it from the battery so it wont drain. i changed the ig. key cylinder and realized that it wasnt the problem, its in the housing, but autozone or any auto parts store doesnt carrie it. whats wrong? pls help. oh, its a 90 gt. thanks!!!
 
There are two parts: the lock assembly and the electrical ignition switch. It sounds like the electrical ignition switch is your problem. The auto parts store should have it if you can find someone who knows how to look it up.

There is a FREE recall on Ford ignition switches. They overheat and sometimes catch fire.

Copy down you VIN number and call the Ford dealer nearest you. Tell them you want to see if the ignition switch recall for Fords & Mustangs was done on your car. They will ask for the VIN number & check it against the master database. If it isn't in the database, then you can schedule an appointment to have the switch replaced for free. The TSB is #95S28, and don't let them tell you that they don't do that anymore...