In email you mentioned not finding the thread. That's probably because the threads that were found were by others. My response(s) are buried in there. Here is a link to the turn signal repair
, last posted to TXBill's new 240D post from last month. This should get you on track with repairing the combo switch.
As for the steering wheel removal. I'm not certain which style of wheel you have, is it the old Bakelite wheel (Hard plastic, large horn ring and about a 5 inch center) or is it the newer style with the rectangular center and soft grip wheel?
The former you have to pop off the center then remove a large nut deep in the wheel. The latter, just carefully pry out the three point star in the center of the wheel, then using a 10mm hex socket (the type with the allen wrench) and an extension, remove the retaining nut. CAUTION: The retaining nuts are on tight, tight, tight DO NOT use the steering wheel lock to counter the force of loosening the nut. Unlock the wheel and have another person steady the wheel while loosening the nut initially. Once the nut is removed , the wheel should just slip off the slines with gentle persuasion (very gentle in the case of the Bakelite wheel).
Hope this helps.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.