Ever seen wiring spaghetti? It tells you how wires and cables are -not- organized, and therefore asking for problems.
Many boats face situations like these. Non-certified people are usually the cause, that wiring systems ends up like this. Finding a problem in a wire-mess is very harsh. A reorganization of any wiring system, who are in a mess is required by marine law. Every boat and ship, has requirements how machinery, equipment and cabling systems should be documented and therefore organized. Please take care of your documentation, and respect the regulations.
It's not only unprofessional and it shows your attitude, how to deal with capital goods. In case of an accident, the boat or ship owner is held accountable.