First of all, thanks for all the great info that you all have provided so far.
After a bit more detective work, I have a little better understanding of what I need. For the liftgate, I just need the exterior handle. For the lower tailgate, I need whatever handle and hardware attach to the mechanism inside the tailgate. After my investigation this afternoon, I concluded that the license plate bracket pivots when the tailgate is lowered but I don't know what it is supposed to be attached to within the tailgate or what parts I need to do this.
So what else am I missing? Should there be a lock cylinder anywhere in this setup?
Here are a few pics of what I currently have.

Looking down at tailgate (top of tailgate is at bottom of picture)
Liftgate just missing exterior handle and lock?