Hi Folks. I'm a newbie so please excuse any breach of protocol. I have a raised Temco (out of business) Louvered Heat Circulating Fireplace (model #TLC42-41, I think, See attached photo.) that I want to remove. I'm stuck on how to detach the chimney pipe in order to pull the firebox from the chase. It has an 8" pipe inside of a 12" pipe. The 12" pipe just rests on the top of the unit and is secured with a couple of screws. The 8" pipe penetrates the outer box of the unit and attaches to a collar on top of the inner box. It is the detachment of the 8" pipe that has me stumbling. It isn't a screw in and it isn't a crimped friction/nesting connection. The installation manual for the unit says, "Push the pipe until it bottoms (into the flue collar, I assume) and the snap locks engage." How do I disengage these snap locks? They cannot be felt if you stuff your arm up the pipe through the damper. I found what purports to be an old ad for this type of chimney pipe on the internet (see picture), but it tells me nothing. Am I stuck with cutting the 8" pipe off of the top of the unit? Thanks.