hi there,this is my first correspondece on this web site.
i dont know if you know this, but the use of stainless steel in contact with normal ferrous steel (as used in car body work,fuel tanks etc) will very quickly cause localised severe corrosion in the ferrous steel due to the dissimilar metals reacting with each other.the only way round this is to insulate the stainless steel from the ferrous by the use of plastic or other type of electrical insulation material. this situation only happens in the presence of moisture,which you WILL get underneath cars.sorry to put a damper on your idea,but you will soon have a holed fuel tank if you go ahead...