It is a piece of cake. For the rear shackles, first loosen the front cab bolts (but keep them in place) put a 2x2 foot piece of plywood under floor and jack up the rear just enough to take the tension off the shackles, then unbolt them. Then replace the rubber bushings and reinstall shackles and check clearance and shim if necessary. The clearance is important for allowing the clutch, brake, and gas pedals to pass through the holes in the cab. A little bit off and they rub on the holes. For the front mounts, remove the bolts and jack up the front of the cab enough to change the rubber squares.
