caravan transmission problem, advice needed

We replaced those transmissions every 30K back in the day. They are problematic. A used one would not be advised. They had issues, and do you really want to spend all that time taking out a bad 17 year old transmission to put in another 17 year old transmission that you have no idea how it's been cared for? Taking it apart and fixing it is complicated, but an interesting project. What do you have to lose? And you get to spend time with your son. They used to leak at the cooler lines and run low, and these transmissions never did well on low fluid. The planetary would blow out quite often. You lose reverse first, then the planetary blows and you lose forward gears. It sounds as if you are almost there now!