I had the same issue when I decided to add cabinet doors to my smoker. Prior to the cabinet doors, my FB was around 105%. After adding doors, it was around 97%. The general consensus from this gang was that it was best to enlarge the Firebox. So I followed the advice and enlarged it to around 110%. Now, my unit runs like an absolute dream. You've already done a substantial amount of work, might as well make it as perfect as possible. Just my two cents. The others will probably know better than I.
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