Transmission flush

My trooper96 4x4, 3.2 have transmission problem and I decide to flush the oil as a step prior to take tranny out. One tranny shop claim they flush oil with the tranny pump and don't use the cooler house. I know there is a connection plug to check the pump pressure, if I connect a line to this plug, were can I connect the other to fill it. Any idea?

I DO NOT recommend flushing this tranny ESPECIALLY if you're having problems, it's a SURE WAY to finish it off completely!

Probably too late in this response, but so few people ever post back that I generally rarely visit this board anymore.