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If that's what they expect from their smoker, it's a very poor design... The heat needs to move to the CC faster so the FB temp is around 300F and fuel consumption is significantly reduced... The exhaust stack "may" have to be enlarged to allow for better air flow... Same with the FB/CC opening....
If you could lower the FB and reconnect it so the FB outlet entered the bottom part of the CC, and add an upper air inlet to the FB, I think you may have a winner...
This could be connected directly to the side of the CC or partial bottom and side would work also... Depends on what you have to work with... The upper air inlet would act as the bellows you speak of... Moving heat to the CC without adding air to the fire..... Thus it would lower your FB temp.... Has worked well for others on this site.... Not on your particular smoker but home made units....
I had the Dyna-glo wide body smoker and a co-worker got the one pictured above. Even with the addition of a welding blanket, I couldn't keep mine up to temp in the winter. The Dyna-glo smokers have very thin metal which makes them susceptible to temperature swings.
I liked my Dyna-glo smoker and it produced some good Q but it's limitations were more than I wanted to put up with so I got a new smoker with insulated walls.