Ric,
Good luck finding UL auto gas on the route. I have found a couple of seldom used strips within range of PHX that have truck stops adjacent to them where I can fill my gas can and pour it in the tank. Other than that UL seems scarce.
BTW the strips I'm referring to are Chiriaco Summit, CA (L77) and Grand Canyon Caverns (L37).
I tried a site that lists UL fuel, but it didn't include these two. When I asked why they said they only list airports where the UL auto gas is part of the infrastructure. Given that the pumps are within 100' of parking at these two strips I think that's an unrealistic filter.
Rich