In post one the ring gear is off. Install the carrier without the ring gear installed and set the carrier bearing preload. Mount up a dial indicator and check the runout. I believe max is .004 but refer to the FSM. If it's out of spec it screws up the Backlash when you check that. You tube has some videos from Toyota Factory rep setting up a removable type pumpkin.
Carrier bearing preload on an 8 3/4” is done 'at the same time' as backlash since it uses threaded adjusters instead of shims (score 1 for Chrysler engineering!). Just make sure final adjustment is to tighten both adjusters as much as possible then install locking tabs and torque carrier main cap bolts to spec.