@NothingClever,
Interesting. Have you seen this done? I'm trying to imagine how this would work. You park your van at a campsite, and then ... what? You let down the passenger window enough to put in place a panel that has the exhaust vent from the room/portable A/C unit plumbed/ducted through? Presumably the A/C unit is set up, maybe strapped down, somewhere behind the passenger seat?
Can you secure the van given that the passenger window is rolled down partially and this panel is in place? (You'd want the van secured while you're on your dive, correct?)
Whenever you need to move the van (e.g., to go get gas fills), do you need to "disassemble" things?
I've been reading about Mercedes Sprinter Van builds. People are recommending choose a (aftermarket) rooftop A/C unit that will function both underway and on shore power (120v). They are saying that the Sprinter's normal (front) A/C can't keep the interior of the van cool enough while underway.
TIA,
rx7diver