I share the reservations noted about carrying gasoline in the car , but if I had to do it...I think I would borrow a page from the management techniques for lab specimens, and provide primary and secondary containment: store the gas in MSR fuel bottles, and contain the fuel bottles within GI ammo cans. Just a thought. OTOH, I ran out of gas in my truck on one occasion in my youth, and emptied most of a case of dry gas/gas line antifreeze into the tank, which mixed with the residual gas in the tank and got the truck running well enough to get me to a gas station. No apparent long term harm to the vehicle, a 75 dodge pickup.