Alright. Here's what I got.
My 6 cylinder fan shroud is spaced about 1" from the upper radiator inlet. Remember the Dodge fan contacted the upper hose, so I'd need to shave 1"+ off the fan.
Here's the Jeep 4.0 fan next to the Dodge 5.9 fan:
The Jeep fan is 9.25" from the center of the clutch to the end of the blade:
The Dodge fan is 10" from the center of the clutch to the end of the blade:
I tried putting the Jeep fan on just for fitment, and it contacts the top of the fan shroud. I measured from the threaded snout on the water pump pulley to the top and bottom of the shroud and it's way off. 8" to the top, about 10.75" to the bottom. It's as if the engine is sitting way too high.
The engine mounts were installed exactly as AA spec'd, and as low as I'd ever want them. In fact, they are a little too low for my liking, but I wasn't going to try to move them.
So even if I cut that Dodge fan down to 9" or less, that leaves over 2" at the bottom of the shroud open with no fan blowing across. I'm not sure what affect that would have on my cooling? I have a little room at the top where I could move the shroud up by redrilling the holes, but I'd estimate that only gaining me about 0.5".