Ok, you asked for it. This is definantly a mod that has not been mentioned, and I would suggest never seen. I got a 4* in a trade and had a HP49 4-stroke I wanted to put on it. The motor, though compact, is quite heavy. I went with a 6v. batt. and was going to have to place it 11 inches back in the tail from F3. As I was devising a mount to place it in the already built tail, that mount turned into a C-channel cage 12 inches long in order to slide the batt. into position. After completion of the "cage" mount, I thought, "I should hook a servo to that!"

Presto...In flight adjustable CG