my pos dutchwest died and while im waiting for parts i want to install my old pellet stove in its place. we just had a 6 inch ss liner installed last year. my question is can i get a 6 to 4 inch thimble and route my pipe into my chimney or do i have to run it all the way up with a flex pipe? its only going to be temporary and i really dont want to hack a hole in my wall for the conventional pellet stove install. TIA