A co-worker has done several Caravan VW diesel conversions. Use the VW engine and trans. Get custom axles made up. Simple and easy according to him, and he says the Dodge service mechanics don't know what to think when they hear it running. As far as I know, all of his were mechanical pump engines, so wiring changes were minimal - glow plugs and fuel shutoff.
Big oil conspiracy lol. I would so rock a TD Caravan, it would be great for the kids.