When I rewired my runabout, the Green Machine, I took out all the old wiring and started again from the battery. In the first video I run a fused cable from the battery in the stern to a pair of bus bars under the dash. Every device is then wired to the terminal blocks there, which keeps the wiring neat and the cables as short as possible.

In the second part I add a stern light, put the battery in a battery box strapped to the deck, spray the terminals to stop corrosion, and run all the wires in conduit cable-tied to the steering cable.