I added two extra shore power cords. One is #10 and the other is #12. They run from the shore power cord box to the power distribution center.
The #10 powers two outlets on either side of the bed and has a third outlet in the distribution center to run the converter or the water heater. The #12 has a single outlet on the drivers side of the bed--and again a female plug in the power center.
The converter had a male plug already and I added a plug on the romex for the water heater.
The same could be done for any circuit.