Thank you, finally I think I got the point
Found a site with some nice and really helpful (at least for me) PDFs about Chrysler part manuals:
http://www.jholst.net/70-parts-manual/Looking at the steering column with the background information I got from you I found this picture. Now I think it's clear for me. The orange wire will probably be the backlight for the column shift indicator. Bulb and lamp are marked in the circle
I misinterpreted the caption on the wiring diagram and thought it's some kind of complicated circuit.
Thanks for the clarification!