Vans are odd. On the one hand, they're frequently associated with high options and premium, etc. On the other hand- there's plenty of 3/4 ton V6 8-1/4 '96+ vans with no air.
They'll absolutely run the gambit to where there's no idea what to expect you're getting until you do. Your 360 may have a 904. It may be lockup. It may have an 8-1/4. Yes, even as a 3/4 and I think a 1 ton as well. It may have a 60, if it does it's likely not even worth adapting to a pickup much less a car. If you find a 318 van it may have a 4 barrel, it may have a 727, and it may have a 60. Starting in '89 they could have overdrive, but in the late '90s it wasn't standard. So a Magnum van may even have the trans you want to use if you don't want an OD. They came in every flavor under the sun and the common denominator was what the person who bought it wanted.
I have no idea if the radiator's the same. Pickups to my knowledge had a slightly taller HD radiator (with A/C usually) that still should clear the hood okay so I'd guess the van rad may be right.