In the west you want to be careful and only work on half the tank. The next station may be closed, out of fuel or may not even exist. All of these have happened to us. Its not unusual to go 100 miles between fuel sources.
Take advantage of good opportunities to fill up, even if you don't "need" fuel, get it because its convenient. Also, sometimes the price is sky high, just buy it if necessary.
When we are in a bigger town, we fill up, it just works out better, you have more choices and the prices tend to be better.
We do have a 45 gallon Transfer Flow tank and that helps a lot. I don't carry extra fuel for the truck, to me its a nuisance, used to do that with the Scout, no thanks and planning should take care any issues.
Good Luck.