2002 46RE part number R5014771AB shows it is for a 2500/3500 5.9 gas engine. Different part number listed for 1500 trans same year and engine.

What if anything is different between the two different transmissions?

Is their any reason the 2500 version couldn't be retrofitted to a 1500 if both are 5.9 gas engines and 2002 models?

@transman you hanging around here still?

The R prefix means it’s a Reman trans.

Besides that, the only internal differences are for shift quality - number of frictions is the same, band material, etc.
Front clutch spring rate differs, a few minor details inside. The case may differ based on if it fits the Durango or the Ram.

If it looks the same on the outside use it.

By coincidence, I saw this after posting I have Cummins coolers for sale.

What is the difference between the Durango and the Ram case???

In 2002 the 2500/3500 was still the 2nd Gen body style , 1500 went to 3 rd gen , dakota I have no clue.

The 4wd durango/dakota has the front diff bolted to the case and the ram is missing some of the bolt holes for that. In order to run a ram case in a dak/dur you have to leave out two of the 3 bolts. I have one on the road like this and i's probably ben ten years and no issues but now I just try to make sure I am building the right case, that first one I had in the durango before discovering the difference. I see no issue running the dak.dur trans in the ram, just a couple un-used bolt holes.