How to remove ignition lock barrel

1989 325i, suddenly the ignition key will not turn past position 1. I removed the steering wheel and covers, but I cannot figure out how to remove the ignition lock barrel. I tried pushing a pin in the small hole just below the key hole, but no luck. Any help?

Well I fixed it. I spoke with a BMW mechanic- he said you do need to insert a pin in the hole while the key is turned- but uncertain as to how far the key has to be turned. Since I couldn't turn the key past position 1, I ended up using a plier to gently force the key to position 2. It worked (for now)... something must have jammed the mechanism. Hope this helps others.