OK, I am going to bypass the parking brake thingy, by grounding the green cable coming from the head-unit harness, and then I have a red/white coming from the C2R-CHY4 that is for the parking brake as well. I guess I ground this lead also?
I am trying to keep the grandchildren entertained on long trips - first one this weekend....
Thanks in advance!
(an old man installing his first car stereo since high school)