You should be able to plot your route down to the fuel location you want to use, based on the approximate route they've provided already. You should already have a good idea of the fuel range of your motorcycle. Thus creating known 'legs' of the run from one fuel station to the next with enough of a 'fuel margin' that extra fuel is unnecessary.
The other item I learned is to make sure you know what your overall average speed is, here's why.
On my second BBG (done as part of the Team Lyle Nevada rally), there was one leg that was getting really close to my comfort zone in range, based on what I already knew about the fuel economy of a GL1800 with >100k on the odometer. Rallymaster provided a
very good tip. Between those locations, simply manage your overall speed by simply
maintaining that value. So, it took me (for 210 miles...) out of that 'rally mode' and closer to a 'touring mode' for that leg.
When it came time later on to run that last 195 miles to the end, knowing what my fuel economy was for that earlier leg made that last leg a lot easier to push as much as I needed to...
...in the Nevada darkness...
...with aux lighting!
It's a satisfying run, certainly!