Thanks, it works great. I have found no need to weld them together. The sheared edges fit together tightly and by the time I got a couple cooks of dripping goodness, they sealed right up. When I want to separate them now, it takes a little screw driver action.
Drilling holes in the pipe would seem to defeat the reverse flow mod; when I've seen pipe with holes it was for a traditional offset stickburner in lieu of tuning plates, not reverse flow.
Got a bunch of cooking toys and a custom metal fabrication shop where I spend my time building all sorts of smokers & outdoor cooking gear.