I was thinking of having my friend that Tig welds build me a fuel cell out of aluminum for my prerunner. The reason is so I can make it any size and shape that I want. But I need to know if you definitely need to have a blader and use the aluminum for a shell, or can you just make the entire thing out of aluminum and not have it be a safety issue.. It wouldn't need to be legal for racing because its a prerunner. What thickness for the aluminum should be used?