I've been planning on installing a wood burning stove this spring/summer. I had my fireplace chimney cleaned today and asked the sweep what size liner would fit down my chimney. He told me he could fit a 6" liner in with some work(due to some twists and turns), given that it's not a straight shot. He went on to say that there was not enough room to wrap the liner with insulation. So my question is, is it ok to install a liner with out wrapping insulation around the out side of the liner. Also most of the stoves I've been looking at have a 7" flue exit. Is it ok to use a reducer and should it be installed before or after the "T" at the rear flue connection.