Installing Baker Insert

My uncle just bought a used baker wood and coal insert. The guy he bought it from just had it sitting in the fireplace with no solid connection to the flue. I already informed my uncle that doing that is not the best idea. My question it due to the fact the steel sheet that covers the fireplace opening is welded to the stove how do you go about connecting the stove outlet to piece of flex liner that goes into the flue of the chimney. Also the outlet on the stove is rectangle what do you use to connect that to round flex liner?

I had an adaptor made up at a sheet metal shop(60bucks) to go to the 6in round flex, also I took the shrould off to connect to the flex. It might work with wood just backed into the fire place, don't think i'd try it with coal you may not wake up in the morning. Do a search for pics.

Cowentz,I would use a pipe to at least get into the smoke chamber or like I did and into the first clay liner and seal it up with insulation to help the draft.I have a Hitzer 983 (insert/free standing cross breed) and thats the way they tell you to install it(put the shroud on it put the insulation between the shroud and the brick or stone and push it up tight with no pipe at all) but I don't like that so I put a pipe on it.I would not burn wood without a pipe,when you clean the chimney you will have to pull the stove to get all the crap out.Barry