Wow Skyriter, stange I only have one A123 pack and it's way back and I never put my wheel pants on. With the stock muffler it was nose heavy, then I put a canister on and I still moved the battery back some more! The wheel pants wont make much difference if I put mine on I wouldn't even check the CG. Also it's OK if the CG is more on the back of the wing tube I don't find this plane so CG sensitive, planes with thin leading edges and thinner chords are more sensitive in my opinion.