Parunuweap Canyon - Advice
(1) Run the route the way we did. If you come in from the Mt. Carmel Junction side, you won't make it up the long steep, deep sand hill down to the Virgin River without EXTENSIVE winching. I'm guessing 4-5 hours to get to the top of the hill in an FJ. Note that I'm not saying that it can't be done, I'm only suggesting that it will be far more work than it's worth.
(2) Air down to 10 psi or lower. (VOLHOO thought to bring sled dogs with him in case he got stuck)
(3) 4WD only.
(4) A winch and recovery gear including axe, shovel and a pull pal are highly recommended. Much better to have and not need than to need and not have.
(5) Take your time. Enjoy the scenery. It's a beautiful run.