There a couple of differences between the van cooler and the truck cooler.
The van cooler has different headers on both ends. The headers are smaller than the truck ones and make the cooler bundle sit closer to the block. On top of sitting farther from the block, the truck headers make the bundle come off the block at a different angle to clear the cross member/motor mount area.
The other main difference is that the oil filter head on the rear header is cast so that the filter sits at a different angle than the truck filter.
The bundles of 4 ring coolers are all the same as are the bundles of 6 ring coolers. So a four ring bundle fits any four ring headers and the six ring bundle fits any six ring headers. The headers have to be used in sets (2 van or 2 truck)
There is another difference in that the van cooler front header attaches to the block with 3 bolts while the truck front header attaches with 4 bolts. If you get the Felpro gasket set, it will include both of the gaskets for the front header (1 van and 1 truck) and the gasket for the rear header. If you get gaskets at the dealer, you'll need to know which one you need for the front (3 or 4 hole)
The mounting area on the block is identical since the block doesn't "know" whether the engine will be mounted in a van or a truck (or a bus).
I added an attachment that hopefully will give you a better idea (stickman figures
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All you really need for your application is the cooler off of a van (really just the two headers since the bundles are the same). Just find a nice engine and we will take care of the rest. There's enough people on the list that have van pieces for you to finish your project