That's a dang good idea too. Keeping the tail weight down is a major chore with a pusher. A lot of times they end up being rather short coupled for that reason. You know of any swept tube spar wings (other then a weedhopper)?Another thought would be to sweep the wing to keep the trailing edge from interfering with the engine. The fringe benefits would be the directional and roll stability from the sweep coupled with any washout giving a bit of pitch stability would allow you to size the tail feathers on the smaller side and save weight, drag, etc.