I only mentioned the big bolt section because that is where the Clark is most commonly found. If any 5 speed was gonna be a direct swap, it would be the Clark. I would imagine when going from an sm420 or sm465 to a 5 speed, there will always be driveline work. Of course I don't have facts to back this up, but a new driveshaft would be needed with the NV4500 or the T5 if you had the sm420 originally.