I also have the Flip3D with a YS 63. My CG fell right at 140 when I put the battery in the front of the fuselage. The plane already is setup for the tank on the CG if you choose to go that route. I did. Why would you want to use seperate servos for the elevator halves when it is not needed. The torque rod setup works excellent and is plenty strong for all manuevers. All you are doing is adding weight and complication for no apparent need. Also if using CA hinges you might want to pin them for extra holding power.