Ignition switch '90 SL

[Hans]

For no apparent reason, the ignition switch will not turn more than a mere fraction of its normal rotation, about 1/2 way to position 1. I can feel a slight change in the steering lock as the key is turned. Have done the usual jiggle, turn, twist, steering, shift lever, repeat many times etc. Have read many threads on general lock removal and watched the video on 129 ignition switch removal http://www.mbca.org/northtexas/repair_videos.htm. So far, most of the info is from non-SL experience. The common theme is that the key either needs to be in position one for removal or use a diamond drill. I have no aversion to cutting/disabling the steering lock if that will help in removal of the tumbler without drilling. Does someone know a procedure for handling this situation? Are there any other alternatives? Are there any serious caveats? Are there any hidden anti-theft or other twitchy mechanisms? Thanks for the help, I really appreciate your time.