KP, your smoker looks awesome!
I used a 13X13 flue. I did put in a upper damper, but wouldn't do it again. I close it enough that I don't have smoke coming out the doors. That way I know the smoke is moving through. With a wood fired smoker I don't see the need for a upper damper. You have a unlimited supply of smoke. Thats just me though. Every so often I get to much smoke in things. Not a good thing on certain things.
Be sure to let it cure out good before you fire it. Start with 4 or 5 small kindling fires before you bring it up to full temp. Can't wait to see your first smoke!
Well done sir!
Well, I wrote this last night and forgot to post it. Old age I suppose...