I did a wiring project on my boat this past spring. Cleaned out a bunch of wiring that wasn't being used and organized some of what was (still a mess but is better than when i bought it). I put a heavy duty bus bar in the back of the boat and ran 4 gauge wire from it to the battery. I then ran my riggers with 30 amp inline fuses directly to the bus bar. My front end electronics (Fish finder, Fish hawk etc) went to a fuse panel that was wired to a switch on the dash then back to the bus bar using 10 gauge wire. Doing it this way with a flip of a switch all my electronics switch on or off so there's no chance of leaving anything on. It really cleans up the wiring that may be attached to the battery as well.