To change the front prop shaft, with the vehicle on level ground, I would put the handbrake and difflock on and chock a wheel to stop the vehicle moving. Then remove the 8 bolts holding the propshaft to the flanges to remove old shaft, then bolt the new one in place, you may have to jack one front wheel up so that you can turn it to get the flange to line up at the axle end. The bolts are IIRC 9/16 head not 14mm.
Pete.