B+ motorhomes

I ended up installing a high-quality marine dual-bank charger in the storage compartment under the oven. I connected it through the floor to the battery relay box under the floor below the sofa bed (rear door TL211) where there is access to both the engine battery and coach battery terminals in one spot. I plugged it into the same outlet that the microwave oven plugs into. I also turned off the circuit breaker for the 12V converter on the factory inverter panel to take that charger out of the loop. Now I have a quality charger that keeps both batteries healthy all winter long without over-charging and it was a short enough run that I could use the charger's factory wiring without extending.