I saw a website that I found a link for on this site where the owner put the tank along the passanger side frame rail. He then cut a hole in the rear fender and welded in a gas door and box kit, installed the filler neck there and ran it down to the tank. It looked pretty nice when it was done.

'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi