If you have exposed fresh pipes they will not make it through the Utah fall. Grey and black pipes will keep flowing with just a bit of RV antifreeze, as long as the days climb above freezing. As said before, rerouting pipes may seem like a pain but it beats repairing pipes.
I think a tenter will be surprised at how warm the trailer stays at night--and how VERY warm sixty degrees is. Add me to the list of people who keep the trailer cool overnight and only heat during the day on demand.
Solar is a great idea but I think understanding your energy usage is a higher priority. Bring extra fuel for the gennie and get a sense of what's required.
Good luck!