First, I have to extend a very warm thanks to those who posted previously about how to remove the ignition cylinder on our MB's. Crazy Nate's thread on replacing the ignition cylinder on a w124 was especially helpful, but there were several posts that gave helpful info.

While those posts were great, I decided to add a little more info to help anyone else who has to tackle this job, or thinks they might in the near future.

First- IF YOUR IGNITION KEY WON'T TURN one time- do this job right ****** now! If you wait, you will quickly find yourself in a canoe up a creek of fecal matter without an oar- if you know what I mean, and I know that you do. My 190's ignition key went from not turning past the "0" position to the "1" postion once on a Friday. It happened just once- but worked fine for 3 more starts over 24 hours. The next day- it took about 10 secs of jiggling, wiggling the key, cussing and sighing before it finally slipped into the glow/start position. Then it rotated clockwise with no problems another 3-4 times. The 190 was then left in the hands of one of our esteemed MB gurus for the next 2 weeks getting its new heater core installed. When I picked her up- he told me to get the ignition cylinder replaced as soon as I could possibly afford to do it. I drove her home and put her in the garage. Next day- 10 mins (not an exaggeration) before the ignition key would turn to glow/start. I was lucky enough to have a few minutes before needing to leave the house to read some posts on this forum. Several posts explained the dire need to address the issue while the key would turn and heeding this advice- I used what was probably it's last "turn" to put the cylinder into position for removal. It took over 15 mins in a 35 degree garage to move it into position 1.

So here are some observations that may be helpful for someone needing to tackle this job.
1. Research the procedure and print it up if possible. Nate's pics were helpful.
2. Disconnect the battery before starting this job. No sense in draining it or glowing while you fiddle with the ignition key!
3. It appears the diameter of the wire for the removal tool is critical. I used my digital caliper and found that the cheapest/flimsiest wire coat hanger from the cleaners was the perfect diameter- approximately 1.8mm. The heavier ones (for curtains, suits, etc.) would have been too thick. My microscrewdriver set was not any help either.
3. My W201 had 2 slots for a "removal tool" but a 2-ended version of the tool wouldn't work for some reason- so I made 2 individual removal tools (one for each slot) and it worked. Also- I had a hard time getting the tools into the groove to do the removal initially. (I think that if you insert one tool, it displaces the cylinder slightly toward the slot on the opposite side. I re-made the tools with a sharper angle- and used a file to de-burr the points and sides and then they went in beautifully.
3. If you are going to use 2 tools like I did- save yourself some hassle and bend some make-shift handles into the wire. And remember the angle in your tool will be facing into the body of the cylinder- you are trying to exhert pressure toward the cylinder. (I think.)
4. The positioning of the cylinder for removal was not the "1" position on my euro 190. It was actually about midway between "0" and "1." So- I used a very bright droplight- and VERY SLOWLY AND CAREFULLY rotated the key counter-clockwise from the "1" position toward the "0" position until the open "passage" for the removal too came into view. Too fast and I could have easily missed the passage or hit "0" and been much further down the previously mentioned creek of feces.
5. When the tool in the top position was indvanced within the slot, there was resistance initially and then it moved freely forward. The tool in the lower slot had resistance the entire time I advanced it forward.
6. I had no idea the contraption was then ready to be removed. The only way I knew it was ready to come out was that I grabbed the key and pulled- and It fell into my hand. It didn't "pop" out for me as it did for others on this and other forums.

So now I've got this thing out and the next stage is to go to a dealer and get another cylinder and key. ASAP. Let's hope it's really cheap...

Oh and before I forget. I called a dealer to get a quote for this job. I told the "shop supervisor" the key would eventually rotate clockwise if you fiddle with it for a few minutes. He paused and said- "we won't do all that- but we can do that job in a day. You're looking at something between $650 and $700." I about fell out of my chair.

Hope this is helpful to someone.
-John