Update:
So I arrived at the Dealership this morning at EXACTLY 99,900 miles (very weird).
Long story short, I did a TON of research and video watching and reading on all of this over the past week. I had the dealership do the Oil Change/Lube...and had them do both the front and rear differential fluid changes.
I've already ordered the supplies for myself to perform the Fuel Filter Change, the Transfer Case Fluid Change, and the Transmission Fluid dump and External Filter change.
I'll be using the Transynd Oil, which I found out I could get locally. And will be doing the double-dump method...which will help get closer to a full exchange.
I hope to tackle this stuff this weekend!
(fingers crossed it all goes well)