Thanks, BG. The idea of re-lining the firebox with some micore, or more firebrick, is a smart one, and may be a big help. Actually, if I covered the firebox in micore and then tiled it, it might make the whole thing look pretty sharp. I think that may settle it--a nicer stove, more heat, top venting ability, etc. Now if I can just insulate that chimney liner...