For years I've had a leak in my rear main seal.  I decided to finally do something about it.
Started by removing the engine skid plate.  This thing was covered with grime
I then pulled the oil pan out.  This was the hardest part of the whole ordeal for me.  My Jeep has a 1.5 inch body lift, and a low profile skid plate (essentially raising up the skid plate an inch or two.  I had to disconnect the mini-cats (exhaust) at the engine, then allow the transmission skid to drop down, and I loosened the exhaust bolts next to the transmission.  After all that I was able to get the oil pan out
You can see that I ended up getting oil and grime all over the exhaust.  This thing smoked like crazy once I finally started it up.
I removed the bottom half of the rear main seal. 
Here you can see a daub of RTV that was added by the factory.  I did the same thing when reassembling this.
It took a bit of work to get the new rear main seal in.  At first I didn't use the included guide correctly (I tried folding it, which didn't work).  I ended up tearing the rear main seal, as you can see here
I finally figured out how to use the guide correctly, and things went much smoother
Finally, I cleaned the oil pan
And put my bolts back in.
All in all it took me two days, working about 4 hours each.  It wasn't a hard job, but it is intimidating, as it's farther in the engine than I've been before.
The end result is good - I do however have a very slight leak still.  Nothing like the way it was before, but still enough to frustrate me a bit.