I just bought my first pellet stove insert. I grabbed a Breckwell P23i insert and I have a few questions. I had to uninstall the stove when I went to get it and I had a few issues. First I could not for the life of me disconnect the adapter from the rear exhaust pipe on the actual unit. I had to grab a hacksaw and cut the pipe right off. The previous owner had an adapter to a 90 degree elbow to a 3" flex up thru the blanking plate. After I cut the pipe so we could remove the insert I noticed that the flex pipe was soooo rediculously filthy. I mean you could barely fit a pencil through! Should I hook up a clean out T? I do have the manual and it does say I can just hook the 3" flex right up to the back of the stove and run it up through the blanking plate but I want to be able to get in there and clean the pipe. Also, do I need to remove the damper? Can I get the flashing material at home depot to use for the blanking plate? Sorry for the ?'s but I am new to this! Thanks