Ok so I am in the planning stages of building an offset or reverse flow smoker.. I live at 5400 feet, and could possible be using this up to 8000 feet. Question is with the reduced air pressure here, what should I do with the calculations for air intake size to the firebox, the opening between the firebox and smoke chamber, and the stack size. I would assume that the lower air pressure would require for all of these figures to be larger than what the calculaters say. Any engineer's input would be greatly appreciated. I want this to be right.