A friend of mine is looking into an Englander NC-13. Are thses only availible in the top vent model? His fireplace is really to small for an insert and he can only afford a small free standing stove. How hard will it be and how much material IE pipe, and thimble will be needed to get the stove into the chimney wall? Is this install very difficult? Mine was a straight shot liner to the insert...Just looking for opinions and advice!