Is that a McCall you made the double door smoker out of? Reason I ask is I picked up a single door stainless McCall reach in warmer & I'm thinking of leaving the insulation in like you did. If your unit has been running just fine with the factory insulation in place, that is a good sign for me. Here is a post with photos of the one I found (and it has a double fan air recirculation system already built in). Also how high have you had that one for a smoke?