I can not decide where to add the fill for my gas tank relocation on my 1945 GMC 1/2 ton. I want to install a stainless steel tank behind the rear end and use the original space as storage. I dont want to add it on the side, because it will take away from the orignal look. I also dont want to add it to the bed, but this may be the only option. Should I buy a gas filler lid and fab it into the steel bed bottom? I work at a fabrication shop, so I can pretty much make anything if needed. Any suggestions??