I have a problem with balancing my 4*40. The plane is completely covered and built, but to balance it I have found that I need to install the battery behind the radio bay bulkhead(behind the wing). Problem is I can't figure out how to install the battery back there. Does anybody have any suggestions as to how to accomplish this. The control rods are in the middle of the fuselage. My last option if I can't get it in the fuselage was to build a cover for it and install it under the canopy. Help please.