Thanks guys.

I don't know anything about the selig S8086 -- which just goes to show you how useful this forum is! I'm going to check into it.

The Eppler makes me nervous. I built a lovely airplane (the 'Golden Snitch') with an Eppler airfoil (168?), and it had a vicious tendency to tip stall - but was it ever fast! So, for no reason other than primal fear, I'll try the Selig first.

I completely agree that building it light avoids a host of problems. In fact, I'm thinking that with the Mossie, the vast majority of the shock loads are going to be through the nacelles. So I'm thinking of an integrated plywood box, (suitably lightened with holes), on which to mount the engines and gear. If I can lock that into the spars, then the rest does not have to be bulky at all. The fuselage really just sits on the wing, and is barely subject to any load.