has anyone with the two battery setup from ford looked at how difficult it would be to install a cutoff relay between them, in order to isolate the second battery as a true "house battery"? is there room in the compartment?
further, could the wiring for the upfitter switches and customer convenience circuits (and perhaps some of the van's other "house"-like circuits) be moved onto that battery? perhaps the bus they're connected to could be physically severed? this would almost certainly be a lot harder than separating the batteries and running the "house" battery to a new panel.
think of this as idle brainstorming -- it just seems a shame (for my uses) to "waste" that battery if i install a separate house system, so i'm leaning strongly toward not ordering the dual battery option.