Working on a 72-914. I’m trying to wire in a secondary oil waning light. The factory small round green light on the left instrument cluster I was planning on coming off that wiring. On the back of that light you have two red/white hot wires connected together that plugs in and you’ve a green/white wire connected which comes from the sending unit. I grounded my new secondary light and it comes on when you turn the ignition on if connected to one of the two red wires but if connected to green wire nonthing! If I connect it to the red wires is that correct and will it give me a signal when oil pressure is low? Thanks

Check continuity from the green/red wire to ground. Pretty sure the oil pressure switch makes a path to ground, when oil pressure is low/engine off. The OP warning light is a very low wattage lamp.

Your right, hooked it up accordingly. Appears to be working alright. Thanks