Norbe,
The measurments in the manual are at the wing tip. It sounds like you are measuring at the root (where the wing meets the body). It would make sense because the first measurment you give is the factory CG and the second measurement is the same just transfered in to the root.

If you are balanced on the wing tube you are close. I also have the Brison 3.2 but with one rudder servo and the ignition battery up front and the reciever battery at the rear of the canopy hatch. It works just fine for me.