The early 722.6 ( 1996 ) had a different valve body and requires a different TCM. The valve body continued to change here and there over the next few years. Mix matching the valve body and TCM will lead to shifting issues.

Also, early trans ( to 1998 ? ) had an external cable to unlock the shifter, later cars used a shifter lock in the car. Even later cars went to a actuator on the trans to select gears / park.