Gasoline and even gasoline vapors do not ignite that easily, it requires a flame, a spark or an incandescent or red-hot material. Headers can be red-hot but only at full load and cool sufficiently during the time to slow down, enter the gas station, stop the car, get off, open the hood, remove the cap, unhook the nozzle, etc....... So even if a few drops of gasoline fall on the header, it makes pschittt and that's all.
But it's still better to be careful and that's why I made this for #4406 which is an L model from September 1972.
