The Federal gov't. crashed lots of trucks to check this and believe me if you get center punched you will die by fire ! the filler neck disconnects and as the tank gets squeezed by the collapsing cab it sprays all the gasoline out in about 1/10th second then your day gets real bad - fast ! the movies of this happening are scary to watch , they used bright red dye in the gas so you can see it splashing everywhere , primarily on the dummy driving . that being said , my old '46 1/2T was center punched on the driver's side bad enough to where I had to scrap the cab (neat spare tire tread marks pressed in though) , filler was on the other side and it drove that way for years .
I keep the tank in the cab , remind me how stubborn I am if I survive the crash .
Dying in a fire is really awfull - you don't actually burn to death - you breathe in superheated air and that destroys your bronchial tubes so you actually suffocate whilst felling the pain of your burning flesh
- sorry but you really should know the facts

-Nate
There is no problem so difficult it cannot be overcome by generous application of brute force & ignorance