stock to autometer wiring

On your original printed circuit board, the blue with white powered the stock gauge voltage limiter and the park brake lamp. The switches at hand brake mechanism and proportion valve supply a ground via the black wire to turn the lamp on.
Just another place that blue w/white needs to go.

I knew there was something about that black wire only being 20G? So if I am understanding you, the black wire is actually a ground that needs to be grounded?? And now I need to feed the parking brake lamp somehow with the blue w/white trace? How and where can I make the connections for this part of the circuitry? I will update the above post where the parking brake is, to reflect the correct information. How should that area read? Hey Thanks....