I'll 'third' that - for a filter / fluid change on the 5.3L, you do NOT have to touch the exhaust (although I'll grant you, it makes it easier to get the pan out). There's a 'trick' to manouvering the pan out / back in - but once you've done it about 3x, you get the hang of it and can move it in / out with ease (there's a double entendre there, I know).
There is (likely) a drain plug in the pan. Bad news is, it will likely be so overtightened from the factory that you run a better than even chance of stripping it (I had to use a bolt extractor to get mine out, and I replaced the pan w/ the Dorman equivalent).
The other thing to be careful about is removing the pan bolts - they can seize, and then snap off. If you notice one getting more resistant as you loosen it, stop and give it a few turns in the other direction (and a shot of liquid wrench can help with this).