What fuel cell fits nicely in the spare tire well 70 Dart?

I mounted a Summit 8 gallon fuel cell in the spare tire well of my 73 dart sport. I fabricated a frame to mount the fuel cell to the floor of the spare tire well out of 1X1 steel angle. Only had to drill four small holes in bottom for 1/4" bolts (mount frame) and a 5/8" hole (fuel line).

Bob