Looks like you all covered most everything. All I would add is a good shovel, and a Hi-Lift Jack. Hi-Lift is not only handy for changing a tire, but it can be configured to pull you out of mud or whatever you may be stuck in/on.

 

good call on the shovel, mine's come in handy quite a few times. not many places on a H2 or H3 to put a hilift without tearing off the plastic, so if you go that route i'd suggest something that will hook into a tow loop and then to the hilift, i think they make something like that. i know they make a tire harnessthat goes on the hilift.

 

I had one set of tires on my K5 that I would take down to 8 PSI. Takes a lot to pop a bead when you mount 12.5" wide tires on a 7" wide wheel.

Here's a nice little web page explaining airing down. http://www.4x4now.com/sfjun96.htm

 

I always air down to 14 psi when I am down in Moab or the Rockies and have zero problem on my stock 33" or my 35"BTGs