47-55.1 Driveshaft & Yoke

[dsraven]

I think what mr48 is saying is that it depends on what you have. by the sound of it I would say your driveline has been altered already, since it is an open rear end. if you have the trans with the attached rear yoke then you will need to install a short shaft behind that which would then attach to another shaft that is held with a steady bearing and then the rear shaft would have a slip yoke on it to accomodate the movement of the rear suspension and the shortening and lengthening of the distance between the rear axle yoke and the slip yoke at the steady bearing end.
some info on what exactly you have for a driveline would help. pics can say a thousand words.