I have a Bunco wood stove I am installing in my basement. I'm going the Metalbestos route and going out my cider block wall and up the side of the house. I have a 10" overhang I have to go around. Can the T-support be shimmed out using treated lumber to get past the overhang? Has anyone done this in the same situation? This is what the dealer is recommending to do away with the elbows. Thanks.