OKLAHOMA JOE'S LONGHORN SMOKER

[BUTCHPETE]

Anyone out there know the "circumference" of the Oklahoma Joe's Longhorn Reverse Flow Smoker? I want to have fabricated 1/8-1/4" thick with the matching opening for the heat to smoker transfer. I'd bolt in place, then mount the firebox in place. With what information I've found, this would correct the weakness from heat that causes firebox to droop somewhat.