would need to know if this trans is a RH or RE model.. RE unit would have a round electrical connector at the case 8 pins.
RH would have a 3 pin connector , usually oblong shape.
RE trans not shifting I would suspect the electronic governor pressure control.
Were the electronics replaced during rebuild?
I have many problems with aftermarket electronics on Mopar trans.. I only use the OEM stuff, especially the governor pressure control
Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.