I have done a few meats in my smoker after completing the mods suggested. I have an issue and not sure of the cause. I have repainted the firebox with the high temp paint but recently burned it off again trying to maintain a 250 degree temp in the cooking chamber. I am sure that the heat in the FB is running much higher than it should be but it appears the heat is not getting to the meat. The smoke is doing fine (1/4 inch to 1/2 smoke rings) and I checked the gauge I added.
Is it possible that their is not enough ventilation to move the heat because of the extension I have on the stack that goes down two inches from the grate? I am almost contemplating adding a fan to help move the heat into the cooking chamber.