Have the backing plates and hoses installed.
Remove the unit bearing. Easy trick to help you to remove it. Loosen the 4 bolts that hold it on. Back them back intil there is about 5 threads deep in the hole. Now put a socket and short extension on the bolt heads and hit with a hammer. It should push the unit bearing out. Once the unit bearing is out. wire brush clean both the unit bearing and the hole it sits in. Next use a flat honing stone and go over the mounting surfaces of the bearing and the spindle. You don't want any high spots that could cause you problems. Put the bolts in the spindle, then the backing plate, then the unit bearing. Now start your bolts and torque to spec.
