It's kinda hard to tell because you need to walk around and look at the other doors to see that none of them fit real well on those vans. But looking just at your photos it looks like the rear side door gap is tighter at the bottom to the quarter. That being said it looks "sprung".
You also want to look at where the latch his the striker and be sure that it will still work if you raise the door up a little. Often, it is all about doing subtle "massaging" of these parts (gentle hits with a large hammer
) to get it all to work well.
Here is a "Basics of Basics" (click here)
to repairing a sprung door that is used by bodymen and auto manufacturers every day. And yes I mean auto manufacturers on the assembly line! I had been doing this stuff for many years, body repair that is. And bending hinges or mounting points, bending door strikers with a smack with a hammer, that sort of thing to fine tune a fit, or to make something fit where you had no adjustments. Many manufacturers have strikers for instance with no slotted holes, they just bolt on solid so you often have to bend them a little bit to make the door fit well. I honestly thought I was doing something "out of the box" and a little hacky when I did this. But you do what you got to do sometimes. I forgot that notion the first time I went thru the NUMMI plant near by where they were building Toyotas at the time. Right there at the end of the line, the last thing on the cars assembly were guys with hammers and chisel like tools whacking on the strikers and sticking a tool in the hinge bending them just as I describe in the "Basics". LOLOL They used a long handled rubber mallet looking tool for the hinge alignment. They used a long handled "Chisel" like tool being hit by a pretty large (4lb) sledge hammer to "fine tune" the door strikers!
So this is a normal form of repair you may do here. Just don't go too far, that's the cool thing. Bend it a little, check if, bend it a little, check it. If you go too far, just open the door and push too far "springing" it again.