Hi. We are installing a woodburning insert. We have put a 6" flexible liner down the chimney (goes to the top & above at the moment). We've modified the existing damper & created and installed the new damper seal panel. We're totally at a loss however to connect the stove pipe (exactly 6") to the flex liner, which is 5 7/8" I.D. and 6 1/8" O.D. This means we can't put the pipe inside or around the liner opening on the pipe itself. We've tried a stovepipe, but they don't come with both ends crimped (male). Please help.