full aluminum tubs?

I'm searching all my dvd's looking for the step by step I did when I made mine -but of course I can't find it. Basically I measured and measured again and ended up with 33" x 16" tubs -cut them out of 22 guage sheetmetal and pop rivet them together- fit them in then welded then together and anywhere they touched weldable metal on the car and along the frame rail -then filled any area between outer 1/4 panel and the tubs with expanding foam. Finished off the inside with carpet