To start off, I don't intend this to be a "how to" so I'm not liable for any misled info on a project like this undertaking. I was looking for a new project and something that had not been done. New and different was what I was looking for. Down the road, I wanted to rig up some sort of anti-wrap bar for my rear axle. Not yet knowing what kind of setup I wanted, I knew that my options would be limited because of where the stock gas tank is located directly in front of the axle. I thought that by moving the location of the gas tank to the rear behind the axle would do two things. It would allow me to put whatever kind of anti-wrap bar in as well as provide more ground clearance under the belly of my truck. What fuel tank would fit in the spot of the spare tire and allow me to run stock fuel injection? I could use a Broncoll tank. I've seen a couple installs as a second/auxillary tank in some EX's. For me though, they hung down too low defeating my second goal for more ground clearance. After much research on fuel tanks I found that I needed to use a Ford tank to simplify things. A full size Bronco tank would fit between the frame rails but is also too tall for my liking 31-7/8" x 22-1/4" x 15-3/4" . An F150 rear tank is shallow enough but too long and wide for my project 34-3/4" x 27" x 7-7/8". What I settled on was a rear tank for a '91 E150 33-1/2" x 23-1/2" x 11-1/8". With my 2" body lift, I measured that it would fit just right in depth and perimeter. With all these measurements, I also was planning to have to relocate the shocks in front of the axle as well. Therefore by any means, this is NOT a bolt in project with all aspects of it being fabricated. If you can weld though, this is a fairly mild project to undertake. Here is the tank out of the box. I started by first removing the spare tire cross bar and upper shock mount by grinding off the rivets. A notch had to be taken out of the body in this area to clear the fill hose connection for the tank. This also shows the rear upper tank mount. Here, you can see the new upper shock mount I made from 2x2 square tubing. I designed it to clear the body by 1". Just before that is the forward tank support. I used rubber hose to isolate the tank from the crossbar/upper tank mount. I made new lower shock mounts to turn the base of the shock 90 degrees so the axle could have more freedom to flex without stress on the shock bushing. Shocks and tank straps in place. Tank in place. Rear mount for straps. I drilled two 3/8" holes in the rear crossmember for the new strap bolts. Front strap crossmember. Slotted holes in 1 1/2" angle steel.