Here's where I am here at lunch time. I decided to use one more little barrel section to meet the flue run, using the barrels as a plenum for the turn around. The whole bench is free of the floor and back wall so hopefully it will convect and draw cool air off the floor and up the back wall. Not much mass in there, but a lot more surface area than I used to have. Looking forward to firing it up tonight when things cool off a bit.