This RV must be on or in a Toyota Pickup, right? A little Class C, right? You don't want to carry extra gas aboard, and you don't need it. I imagine you'll find you don't want to drive this above the low 60-mph speed, and I imagine you'll find your range is close to 200 miles before your gas is frightenly low.
I just checked with my daughter. They drove a Subaru Forester from OK City to Anchorage AK in late spring. This means not all the gas stations along he AK Highway were open. They carried two 5-gallon plastic gas cans on a rack at the back of their heavily loaded (read Over Loaded...) popup camper. They were only getting about 15-mpg. Subaru's tank about the size of yours. They NEVER needed any of the extra fuel. All it did was damage the rear bumper of the trailer with the extra weight.
Come to think of it, a friend bought a Toyota-based Class C in AK and drove it to FL. Never complained about a gasoline crisis.
You will be simply JUST FINE! Welcome to Forum, Congratulations on your RV, Have a Great Trip, and Keep in Touch.