Hunted till noon then helped a friend instal his 6 inch liner. Not quite the piece of cake I thought it was going to be. 6 inch liner. 12 inch square chimney. 4 inch stepped and offset damper. we ovalized 26 inches but that wasn't enough to get it thru the damper. Demolition bar and 8 lb sledge did the trick after trying just about everything else. Had to take 2 bricks off the front of the smoke shelf. took about 4 hours. 2 hours ago the phone rang. Another warm familyu enjoying a fire. Don't forget the tube of caulk when you start an install.