I replaced my water heater which was outboard of the port motor. It's a 41C Galley up and I took on the task
when the motor was being rebuilt. The head was off and the old unit came out right over the top. I
installed the new heater, prior to it's removal, under the sink. It's a piece of cake to service and
winterize. Their is still room for storage under the sink and the heater ( 6 gallon ) slides under the
sink trap.