To make room for the 4-link it was necessary to move the gas tank. The V8 S-10 guys do the 2door S-10 Blazer swap to accomplish this so I figured I'd do the same so I wasn't reinventing the wheel.
First we removed the bed:
It actually worked really well to use my engine hoist to remove the bed.
Then I removed the rear frame crossmembers:
I fabricated new crossmembers to support the gas tank. The rear one was trickier than it should have been because I had to make the leaf springs work for a few more weeks. I'll add another gusset like the one on the top to the bottom once the leaf springs are gone.
Next I installed the gas tank support straps.
Then I strapped in the gas tank, extended the fuel lines and wiring. The old tank was removed and I modified the exhaust for a temporary solution until I get the 4 link in and figure out where everything fits. For a sanity check I hooked up a battery and started the truck at this point with 5 gallons in the tank.
The last step was to make a way to fill the tank. I cut the gas door off the front of the bedside (action shot!).
Then I picked a spot behind the wheel that was close to where the filler neck came out of the tank and welded the door in. I managed to cut right across the hinge for the door when I cut it off, so I had to grab a door from the parts truck.
I had to notch the frame a bit for the filler neck, I'd be more worried if the leaf springs were staying, but since they will be going away in a few weeks this will be fine.
I also had to notch one of the bed supports to clear the fuel pump and hoses.
The last step was reinstalling the bed and modifying the filler neck.
The new gas door has a slot to hold the gas cap, the old one used a plastic cable that broke off years before I ever owned the truck.
The tank hangs down a bit, but it's not too bad. I still need to make a skid plate for it since I know I'll be dropping the truck onto it.