I would like to add the tach from a 300D to my a983 240D. I can get the tach/clock from a junker. tach has balck/red and green/black wires attached, but I cannot follow where they go to pick up the signal. I have a bunch of 240D wiring daiagrams and service books, but not for 300 that shows tach. Any ideas what else to get off 300 junker? Anyone have a wiring diagram for 1985 300D turbo?