here's some pics of my file cabinet smoker. Made a mild steel inner for it and insulated it with thermal rockwool. Inner is pop-riveted onto file cabinet, door fronts and backs are pop-riveted to each other. Gave it a good season with the gas burner up full, temps went off the scale 550F +, and the build and doors didn't warp phew..... filled in a few smoke leaks with chemical metal.
Temps are varying between 250-300F with the burner at the lowest setting and the drip tray filled with water. Better too hot than not I can cover some of the burner holes If I need a real slow cook and blast her up high for a tandoori style cook
Happy its all over now the fun really starts