The only issue that I'm aware of in regards to swapping 46r transmissions is the earlier ones are controlled via intake manifold vacuum while later ones are controlled via the computer. I'm thinking one can work in place of the other but not the other way around, but I can't remember which way or even if this is true or not.
However, being as your Ram and Durango are '02 and '99 respectively, both should have the electronic-controlled transmission and this shouldn't be a problem.