If you go through Mt Isa when going from Boulia to Cloncurry you will have bitumen roads all the way. A lot of it will be narrow bitumen surface. The only fuel problem I foresee is Winton to Boulia, that is 363 km.

To get a handle on fuel availability I suggest you use Petrol Spy. The site is mostly user maintained but for the Qld and SA prices, there is cooperation with the state authorities for short time updating of prices. If there is no entry in the database for a town then it is most likely there is no fuel in town. On the other hand, have a look for the update time in each entry, if it shows more than one month ago then fuel may not be available. Ring ahead to check on availability.