you will need the belt side motor mount off the original motor and bolt it to the z6. Also put the water neck on the original motor on the Z6 it makes it a lot easier to run the upper hose. The original trans will bolt up to the z6 but you will need to install the clutch and flywheel to that went with the original transmission.
Did you get a OBD0 to OBD1 conversion harness?