I'm not a long time Jeep owner, but I work on vehicles alot
engines are easy to break in. in addition to that, the gears in you axle need broken in.
-don't maintain the same speeds. meaning no cruise control for too long. run it at 70 for a few miles, then drop it to 60 a few, then 55, then 75, etc. skip it around a little. move those RPM's.
-don't redline it, tow, or do anything crazy offroad. take it a little easy.
after 1,000 miles you'll be ok. no worries. basically, you're already past the break in. check for leaks, strange engine noises, or noisy axles. nothing? you did it right
it's pretty hard to screw up a modern engine with improper break in.
now, at 3,000 change your oil no matter what. this is when you'll want to choose your oil type. bulk, bottle, synthetic, etc. I watch it close for the first 3 oil changes or so. i do this to get an idea how the engine and oil will play together. watch for high oil consumption (JK's burn 0-1/2 quart every 3,000...this is normal) but anything more may be a problem. you know that smell after you change the oil? pay attention, and make sure that leaves after a bit.
that's it. basic, easy stuff. most folks do all of that without even knowing. you'll be ok, ya worry too much :P