Ok, let's go with two gauges: one oil pressure and one fuel level. I do not have the sending units from either. I'm fairly certain that the oil pressure one is an electronic signal sent from a unit under the hood. It is not inconceivable that I could get the transmitters but in the end there's only a certain amount of energy I care to expend going down this avenue and trying to find those parts might exhaust that. I can still accomplish most of what I wanted to regardless of the electronics as the 24V thing is mostly going to be disassembled and used for architectural components; it just would be pretty handy to use these two gauges from the unit.