BMW: ignition, proof screws, haynes manual

Question
Hello,

I have a 1989 BMW 525i with 300k, all my miles, car in very good shape. Recently I placed the key in the ignition and was unable to turn it. Should I replace the ignition switch or just the ignition lock cylinder? I have had no trouble with the ignition.

Is this something I can do myself (I have recently replaced the brakes...dics and pads), using my Haynes manual?

Answer
When i get this complaint i replace the steering lock collar and lock cylinder, because guess what? if you cant turn it you cant get  it out of the housing and i have had zero luck drilling the things. You will need your drivers license and registration to order the lock cylinder when you go to the dealer. It has tamper proof screws holding the collar on, you need a hammer and chisel to remove them.