I flew it with the OS.25 VFDF/Axiflow, and the OS.46 VFDF/KressFan, assuming I was dealing with a thrust issue. I played around with spinner fairings, etc. The plans originally showed a cheater hole on the bottom, just fwd of the spar if I remember correctly. I later found out (after getting rid of the model) that it was a CG issue. The model would "hang" literally at about 45 deg AOA, with no effective roll control. It was bizarre. I think I was eventually able to fly the model, but this was also around 1990. I probably still have the drawings. I could check the drawings and see where the CG is shown, then see how it corresponds with your location. From what I remember, the MLG will then be a bit aft. They appeared already aft even with the model I built...