Spotted this on my way home today. It's a 250 (3/4 ton) SRW - long wheelbase, high roof, v6 non-turbo, not extended length. It has a sticker of $35k.
This looked pretty base, so they go up from there.
In person, these look better than in pictures. Similar inside to the Promaster size wise. Much higher step in, floor all one level and overall a taller van - looks around 12" taller.
Underneath, there is some space for tankage, but not what I expected. The fuel tank takes a huge amount of space in the center of the van. So tanks will need to be long and narrow.