So I have installed a Airjet triple wall SS chimney system thought the wall in my house and am having trouble with getting the stove pipe to attache to the T snout that comes thought the wall. The pieces seem to be the same diameter. I have a 90 elbow and the big end slips right on the T-snout but the black stove pipe does not fit at all. When I was buying the stove pipe I noticed they had a slip joint section on the self, is this what I need to mate to the T snout? Also waht way should the seem go on a horizontal section on the top or bottom of the pipe? Thanks