I'm wiring up a Speedhut oil pressure and water temp gauge and I'm wondering if I can wire them directly to my Blue Sea fuse block for an ignition source? I've tapped into the cig lighter for a USB plug, if I can't wire the gauges to the fuse block, can all 3 be tapped into the cig lighter wiring? Last question (for this round), the wiring diagram has an inverter and both gauges can be plugged into one inverter. Do I need to connect the additional ground and dash lighting cables or can I use the one connection that both gauges are plugged into for the dash lighting / ground?
Inverter
Inverter