Well now those are a couple of very nice installs. I did mine a lot simpler, without cutting the spare tire well out. A ten gallon cell will fit into the existing well, all you need is a way to mount it. I made a framework out of square steel and welded that into the tire well, then bolted the cell to the frame. I also used a couple straps for safety reasons, to keep stress off the mounting tabs of the cell.
Here's the frame in the well:
Then I bolted the cell to the frame:
Since I have a hatch I needed a firewall so I built a frame for it from square steel tubing and skinned it will sheet metal:
Here's the finished product:
OFR - old fart racing
We're not fast racers. In fact folks call us half fast racers. At least I think that's what they're saying.