thanks Andres, this is wonderful info. I'll order some.
As to your issue Allen, my car ('66 230SL) is not even running, nor do I know of it's electrical issues, I've never had a battery in it. But I do know those can be made to work.
When imported to the US there were many things done to all these cars. Some of the wiring is there, but never connected at the factory.
I have a 1971 220D which would not flash its headlights when the turn lever was pulled. I knew that worked on a '74 240D that I once had so I went looking on the '71. The wiring diagram shows the connections to the steering column switch, and my headlight wire was there at the switch, just no power. Back at the fuse box, I could see that the wire did not make to to the proper fuse. Taking the box hold down screws out, let me look under the box, and there was a harness with all the wires. Careful inspection showed there were two layers of tape at the end. Unwrapping the first layer uncovered the wire for the headlight flash function, doubled back on itself. I connected it to the proper fuse terminal, now that car's lights will flash properly. I see that my alternator wire has a double wrap tape, with a doubled back wire peeking out. I think it is power for the A/C compressor, which the car does not have, nor did it ever have.
I assumed I was going to have to do some looking to get the headlights to flash with my 230.
On the fog lights in the 220D, you do have to pull the light switch out one notch and rotate one click for front fog lights. I have euro lights on it and they work. Additionally, there is a second pull out notch used to light a rear fog light. With the rear fog light on, there's a green light that comes on in the center of the dash knob. On my 220D, I had to wire that green light to the proper terminal on the light switch, and I intend to put the rear fog light on the car soon.
On the 230, I don't know if they ever used that light switch knob with the little green light in it.
BTW, I think German "fog lights" mean something different that my traditional definition. All the M-B lights seem to just be serving as bright marker lights, not really, lighting the way as the US off road "fog" lights do.
Ron