All three can be wired in series..post to post to post for ground,power,lighting power. All three grounds in series to any body bolt for ground. Power to the gauges can be run post to post in series as well to any "ignition on" power source. I used a tester to find an ignition on 12v power fuse and inserted the wire with the fuse..this wire sent power to both (in your case all three gauges). For lighting power I again wired in series and had the wire run to fue #13 which is the lighting dimmer fuse. As for running into the bay, simply run through the grommet in the drivers side of firewall and run wires neatly to required senders.