For those interested in pics, I have some of my chimney here: https://www.hearth.com/talk/threads/feedback-on-c450-insert-install.99803/ I was up on the roof and measured my flue before I get a SS liner for the installation of a Jotul C450 insert. It is tight - probably 7x11. The stove has a 6" connection. My chimney is 14'8" from the top of chimney to bottom of fire place. The stove is 22" tall, so the effective height would be around 12'10". I'm worried that the 6" liner won't fit so I have two options - ovalized 6" or 5.5". Can anyone comment on if I can get away with a 5.5"? Can I make the 6" work? Any input is greatly appreciated!