Merry Christmas, 6XCHEVY,
The one advantage of doing it as you describe, is that you do not need to open/disconnect the torque-tube connection.
Yes, alignment of the transmission front/pilot shaft to the clutch is a consideration. There are a variety of ways to deal with this. Here are two ways:
I look at this as a 2-person job (maybe someone will correct/clarify).
1. put the transmission in neutral
- remove the inspection cover from under the clutch housing
- "jimmy"/rotate the flywheel to align clutch to front/pilot shaft (using a prybar or large screwdriver or rotator tool in the teeth of the flywheel)
2. put the transmission in gear
- raise the rear of the truck and put stands under the truck (first: chock both sides of a front wheel)
- have a friend/spouse rotate a rear wheel (and hope it rotates the drive shaft)
If your u-joint cover is leaking, you might as well remove the transmission (get a gasket/seal kit and follow the adjustment instructions in the Shop Manual).
If my logic is faulty/unclear, someone will correct this.
Good luck.
