What a mess. You can see, from the pictures I took when the blog started, the 12 Volt wiring was a complete mess. It looked like two octopuses trying to mate in a wind tunnel. So, the first step was to remove everything from the bulkhead, and paint it white. I use a moisture cured polyurethane paint from Wasser. It is expensive, at around $125.00 gallon, but it applies in one coat, and is almost indestructible once fully cured.
I then re-routed the battery cables into sealed, ventilated compartments located on each side of the freshwater tank, so I can remove the batteries from the engine room. Before anyone considers duplicating this modification, there are a few items to remember:
1st - Conventional flooded lead acid batteries vent considerable amounts of water and acidic gas. I have changed to sealed AGM style batteries from Optima. These batteries recycle almost all of the water and gasses liberated during charging, and therefore do not contaminate the compartment with acidic fumes.
2nd - I have vented each compartment back into the engine room.