I have a King Kobra and it requires basically no elevator to fly inverted. Here's what I would do. Check the thrust lines by flying at a 45 degree and then vertical angle. See what the plane does and adjust the thrust accordingly. Also, those incidence readings don't mean too much because I'm sure the carved leading edge is not perfectly semmetrical so experiment with some shims. Finally, move the CG back a touch and also check to make sure those push rods aren't bending under load (maybe full elevator on the stick isn't really full elevator under load).

Mike