I have an existing wood in a space that is about 9ft wide. Depth of the space doesn't matter with the wood stove, but if I were to install a RMH I could only get about 3ft. of depth because of existing doors. I have read what I can and my guess would be that this is not enough room and that you can not have your piping snake around too many corners, let alone above it's self.
Allen; You did not mention what existing chimney arrangement you have. When your pipe leaves the mass and goes vertical it does not have to be directly under your roof jack, the exhaust temps will be low enough that you can run your pipe close to surfaces that a normal wood stove could not.