I have purchased a USB 12 V device that I can mount about anywhere on the bike, but I’d rather have it on the dash itself. In doing a little exploring I popped off the cover where the oil pressure gauge could be installed. Behind the cover is a plug. The wires are orange blue and purple going into the plug. What I’d like to know is which one of those is the ground and which one of those is the positive wire. I think this would work out well as it’s tied into the ignition system and shuts off when the bike shuts off. Any advice you could give me would be very helpful. Thank you, Peter.