BBQ Engineer's thread on his reverse flow has me thinking of having something similar built (a little narrower but a little taller, like a veritcal cabinet cut in halves). I know he was using 10 Gauge in his build, resulting in some weight being there. As I know some of the cabinet makers (Stumps, Backwoods, Spicewine, etc) are "light" units, my question is what would be the minimum thickness you'd want both internally and externally for a build? I was thinking of doing it in 11 Gauge internally (heavier on the fire box) with 14 Gauge on the outside, but if it could even be shaved down to 12 & 14 or something else, the weight savings could be nice. Any inputs / thoughts would be great, as my knowledge in this area is lacking.