Got my new oil pressure gauge, prosport stepper motor gauge, the instructions definitely arent clear enough regarding the wiring, theres 4 wires for the power that plugs into the back of the gauge. theres red, black, white and amber. Guessing red and black are live and earth, not sure what the others are for! says what the wires go to: Black - battery (-) red - battery (+) amber - Note white - Note anything? anyone?