Hi Mike,
I have a love/hate relationship with cars like yours and many others, including those I saw up close at PUB2015. I love them because they are beautiful and provide incentive for me to finish mine. I hate them because I'm jealous that mine is so far from being finished - springtime at least.
Anyway, today I finished a project that I didn't expect to do at all. Earlier this week, I pulled my 1966 or 67 (not sure which) 230SL steering column off the shelf to reinstall it, but when I turned the shaft, it sounded and felt like someone had filled the steering shaft bearings with sand. I am amazed that there is so little detailed information in our TM and in the BBB, Haynes, Chilton's and even on the other Mercedes sites regarding the insides of the steering column. There's lots of stuff on the steering wheel and steering gear, but not on the column insides.
I pulled off the Steering Coupling near the Steering Gear end of the shaft, then the Multifunction Switch and then pried off the Horn Contact Ring. All fine so far, but then I unscrewed the two socket head cap screws that hold the Bearing Ring to the column. I heard lots of metallic tinkling sounds inside the column housing as parts dropped away from the Bearing Ring, deeper into the column housing - to wit: the two pieces of the Lock Ring, the two small springs and the two large square nuts that hold it all together on the ends of the socket head cap screws.
I had no idea how it all fit together, so I went to all the above resources to find out. No Luck! Even the EPC sketches are too small and without enough detail to help.
Anyway, I cleaned everything and inspected and repacked the upper and lower bearings, then I even unbent the tabs, disassembled, repacked and reassembled the the little stamped-race bearing between the steering wheel and the horn contact ring. All the bearings were dry and rattled, but not damaged at all.
I even remade the nylon washers and fitted some other washers to rebuild the Steering Coupling, since I couldn't find them anywhere. Wasted gas and google time looking for them.
Finally, this afternoon, I got it all back together and the shaft turns smoothly and so silently that I can not not only see and hear the turn signal return perfectly equally in both directions, but I can even hear the tiny turn signal tab re-cocking itself when it reaches the point where the turn signal will return once the wheel is turned back to almost center. The centering of the wheel and the turn signal return points are much better now than they have ever been, at least since I bought it in 1987.
Unfortunately, I didn't take any photos, so if anyone decides to take on this project and needs help, I'll be glad to annotate your photos to help put it back together. I'm not going to take mine apart again just to take photos. The Lock Ring pieces with the square nuts and springs are not difficult, unless you don't know how they are supposed to be oriented. It took me two or three hours to figure it all out with several restarts without any documentation or pre-disassembly photos.
Don't hesitate to ask if anyone needs help.
Tom Kizer