To change the clutch in a Massey Ferguson 12 Baler, you will need to first disconnect the PTO drive line from the output shaft on the back of the baler. Detach the drive belt from the clutch pulley, and then remove the nuts from the pressure plates to the flywheel. This will allow you to slide the clutch out of the engine housing. Once the old clutch is out, you can slide the new one in. Install the pressure plates and reattach the drive belt, and reconnect the PTO drive line to the output shaft. Be sure to make sure all parts are securely fastened before testing the clutch.