goldenclan, Don't worry too much about the CG on the UCD46. The factory offered an addemdum to the manual which states you can balance the plane anywhere between 4 and 6 inches from the leading edge and still fly fine. I run mine about 5 3/4" It makes it 3D a little bit better but is still ridiculously easy to land. Such a fun, fun plane. Anyways, I wouldn't bother trying to move too much stuff around. If you are in that range you are good. Has a longer CG tolerance than any plane I've seen.
Thanks,
Barry