This small maintenance project is done. Really simple and I didn't have to remove the spare tire. The upper plug had no debris build up. The low plug had a very small amount of debris build up -- just enough to fill the concave cavity. I attribute this to normal wear and tear. Refilling the diff, at first I tried to squeeze the fluid through a short length of tube. It worked but I got sick of squeezing the bottle and broke out the fluid transfer pump.
I used about a bottle and a half of the Mopar friction modifier and just about 3 bottles of the Mobil 1 75W-140. I also applied a little high temp black RTV onto the plugs to seal the threads and torqued them to 20 ft-lbs. Went for a ride -- took it slow and easy at first and then visited a local parking lot. After several launches, back to the road for some more (faster) driving and then back home (slow and easy). After road testing, no leaks, no rattles, no grinding, whining, etc. Finished...