been a few months since this thread has something posted so don't mind if i do. i remained patient scouring craigslist for several months until i finally found something i could work with. found a lightly used
chargriller smokin pro for $50 and promptly went to buy the add on fire box. after being freshly assembled i took it for a test run and discovered where the flaws are. here's the mods i've done so far:
got a buddy with access to a sheetmetal shop so i asked him to make me a new charcoal box, measures 12"x12"x6"
ran some all thread though it and here she is hanging in the sfb
i asked the same buddy to also cut me 5 plates that are 13.5"x6" and bend a 45° bend 2" in on one of the plates, using these for tuning plates/baffles. i bolted some aluminum L brackets to the front and rear of the main chamber to set the plates on then bolted the baffle with the bend in it above the inlet from the sfb
riveted a 3/8" C channel down each side of the main chamber and stuffed some 1/2" fire rope in to the channels to seal up the sides
replace the worthless stock temp gauge with a steel piggy and then put a couple new temp gauges in the lower left and right portions of the lid near grate level. the temp gauges are
http://www.homedepot.com/p/Brinkmann-Temperature-Gauge-812-7229-S/203016476 and though Brinkmann Support posted in the question/answer section saying that the gauge is not adjustable, they actually are
added some dryer vent tubing to the lid. just used some large channel locks and bent the flare in until i could slide the tubing on to it. it's bolted to the side of the lid
i've also used red rtv to seal up between the sfb and the main chamber (took the two apart, applied the rtv then bolted back together), used the rtv to seal up the plate behind the pig that replaced the stock temp gauge, also used the rtv to seal up around smoke stack. still to do is figure out how i plan to seal up the front and back of the main chamber, probably going to use a L bracket riveted to the front and using some rtv to lay down some flat fire rope to it. the back though???? maybe just lots of heavy duty foil for now. then on the sfb i'm planning on using some rtv to lay down some more flat fire rope around the main door and installing a hook latch to pull the door tight and keep it sealed