[Tommy]

Rob,
I wired everything in my car myself and here is what I did. My battery is in the trunk, so I ran two 4 gauge cables from the battery ground to the frame (in the back) and the engine. I ran a 2 gauge cable from the battery positive to the lug on the starter. I then ran a 4 gauge cable from the starter lug to the master power switch on the dash. Power for everything else comes from the ON side of that power switch.

My car was originally a full competition race car, so I kept many of its race car features. One of those features is toggle switches with built in circuit breakers. This allows the driver to quickly see and reset a popped circuit breaker by simply cycling the toggle switch that protects that circuit. It also means there is no fuse block.

The lights are the only system that is a little more complicated. Because all of the gauges have back lights, I mounted busses under the dash for the positive and negative cables to the gauges. And I wanted a button on the steering wheel that would switch the headlights from bright to dim and back. I designed and installed a system with a latching relay that alternates power between the bright and dim circuits each time a button is pressed. Each of those circuits has its own relay to carry power to the lights.