A lot of mailbox mods use 3" alum pipe fittings because the Mes digital smokers have a 3" chip loader hole and top vent. If you did do a mailbox mod, you can search SMF, a 3" T fitting hanging from the bottom of the analog smoker, since there are legs elevating the smoker, would be a good place to plumb in to collect grease and let smoke in through one hole in the bottom of the smoker. This is mine because of the 3" side chip loader hole. Yours could come in at the bottom from a T and drain grease as well. I don't know how to post drawings.I get the top damper and the rain cap, but the part about the "T" and mailbox mod is extremely confusing to me....and I do tool and die for a living lol.