Anyone have a source for a PDF or whatever of the dash layout of a 1967 W111?

The dash in question is from a W111 250 Coupe so the instruments are different from the normal W111 but the instruments I can figure out. There is what appears to be an emergency flasher switch to the left of the steering wheel and then there is to the right of the ignition key a rheostat. What does this rheostat operate? The brightness of the dash lights?

This is a Euro car if that makes any difference.

I am not totally ignorant of the W111, but this is the first coupe I have ever had to deal with. The owner asked me to help him figure this stuff out so I just posted here since I know the questions to ask.

I can't get a photo out of him as I am doing all of this by phone.