Hi. Long time lurker first time poster. I talked my neighbor into buying the Char-Griller fire box to attach to his CG Duo. I have read the mods for the smokin-pro and duo which usually include some type of baffle. I am contemplating cutting the hole smaller than the knock-out to eliminate the need for a baffle and turning the charcoal pan up-side-down for dispersion. The cooking chamber on the Duo is much smaller than the smokin-pro but has the same size knock-out. I am thinking that would be way too much heat. The fire box has a round damper on the end that would attach to the chamber for using the fire box alone as a table top grill. At a minimum I was thinking of leaving this damper open and cutting an equivalent round hole in the cooking chamber. This seems like it would not allow for enough flow. The next step up would be to cut out the entire round damper with equivalent round hole in the cooking chamber. I am thinking that this would be a good starting point but still concerned that it would not allow for enough heat or flow. The next step up would be to leave both knock-outs in place and cut smaller, say half the area, out of both football shapes. Does anyone have any insight into the best size opening? Any optimum positioning of opening as in low on chamber if not using the whole knock-out?