Here's a wire mapping from the new gauge, to your stock colors. You will need to install diodes for your turn signal (on the stock harness to that gauge).
Gauge Function Stock Color
Yellow Turn R Lt Blue
Yellow/Black Ground Green
Green Neutral Black
Green/Black Neutral Ground Green/Red
Blue HI Beam Blue
Blue/Black Ground Green
Red Oil Pressure Green
Red/Black Ground Blue/Red
Yellow Turn L Orange
Yellow/Black Ground Green
A little explanation:
On your stock harness, BLACK is switched 12v (power). The new gauge has LED lights, and each LED light has 2 wires; a power and a ground. The /Black color wire on your new gauge is the ground side foe each function.
The OIL and NEUTRAL lights are looking for the signal from your stock switches, and you run the stock /Red wires to the GROUND side of the LED. You run BLACK (power) from your stock harness to solid color (you are reversing the logic on the rest of the wires).
You'll notice the YELLOW gauge wire has only 1 input, but serves both sides of the blinkers. Thats why you need a diode to prevent the R signal from igniting the L side when active. The diode is a 1-way power flow restrictor.
Most of the wires you need are available from your stock handle bar clamp, but you will need to tie BLACK into more lights now, and GREEN into more wires now (since your gauge has so many "functions").
Before you begin, make dead certain you bought the correct gear ratio for your model of CB.
