I recently put a new radiator in my jeep and cannot get the transmission cooler lines to seal! Has anybody else had this problem?

Hi Guys, I'm posting this all the way from Australia Hopefully some American Jeep knowledge will get me back into mine again. I basically need to know if a 96/97 42re transmission will fit into my 98 4.0L Grand Cherokee. I've heard that different models ran different computers and TCMs so I'm...