IM BUILDING A NEW SMOKER- FIRST TIME OTH\ER THEN OLD FUEL BARRELS -IVE GOT A STEEL BOX 3/8 PLATE STEEL 3' DEEP X5' WIDE X6' HIGH- IM THINKING FIRE BOX SHOULD BE 24 X 36 X 60 WITH A 32" OPENING TO PIT- ANT THOUGHTS ON IF THIS WOULD BENEFIT BY MAKING IT REVERSE FLOW? ANY SUGGESTIONS WELCOME