Give up on the "the don't pass gas below a quarter philosophy". You have at "least" another 6 gallons of fuel in the tank before you have to worry. That is another 36 miles by your math.
In the old days gas gauges were not very accurate, and gas stations further apart.
It's different now. Plan your trip out. Decide how often you need to rest. How many towns are along the route. And quit worrying about running out of gas.
On my 2004 Chevy pickup I tested it out and had a friend follow me with extra gas. I can drive 25 miles after the low fuel light comes on. Maybe, even more !
I just chickened out after that many miles and that is when I got to the next town anyway. Most gas stations in my area are about 25-30 miles apart.