Wired by a Kindergartner

[kb79]

I'm in the process of preparing my boat for a 2yr South Pacific cruise, and one of the (what I thought was minor) items on my "to do" list was diagnose and repair a problem with the starboard reading light in the salon.

The problem ended up being that the wiring to this light was unsecured as it ran behind the main bulkhead, and the wire chafed and shorted. The chafe point was a second wire, which I opted to replace as well. Herein lies the rub...

That second wire required removal of my breaker panel, and I'm in absolute shock - it's a total rat's nest, complete with duct tape, lose wires (that apparently are no longer being used, and are attached to nothing), red wires heading to ground, literally 13 grounds piggy backed and not a bus terminal in sight.

So, looks like I've got tens if not hundreds of hours of unforeseen work as I completely rewire the boat. I don't see any other alternative (but would love to hear one )

I'm not sure if I've got a specific question, but I'd welcome any general advice. Any hot tips that might save me some time? Specifically, any great advice on how to trace wires that disappear behind panels and (as far as I can tell) do nothing? I'd like to remove unused connections, but I'm not sure how to trace to the other end of the line to verify that, in fact, it's unused.

I know my way around a mulitmeter (don't need advice about checking for continuity, etc), and have done a bit of wiring in the past but nothing like this.

The attached picture isn't of my boat - mine looks twice as bad.