Lyle Larson (
http://www.angelfire.com/ok2/racewithme/lylepage.html ) has, or at least had, a Midget Mustang kit for the .40-size Formula 1 event: 450 square inches, 7" x 3" fuselage cross-section, 5 lbs. all-up. I'm holding one of these for a buddy, framed up and ready for paint with a Rossi .40 installed. If you're interested in an airplane at this stage of construction, send me a PM and I'll put you in touch with him directly to negotiate a price.
Duane Gall
RCPRO