Moin Chris,
the Transmission you are looking for has the code CBN. It´s pairing Differntial has the code AXZ.
To make your car even rarer you must do ........ nothing. The combination of 4,2ltr engine with 5-Speed gearbox ist the rarest possible (even though not original).
The only problem is durability, because the 5-speed gearbox can´t stand the torque of the 4,2ltr (and the 3,6ltr as well). This was the reason to change to the 6-speed gearbox.
From this point of view: change to 6-speed.
