i have the previos version just before yours, Not sure if the cg in the manual are the same. I have mine at 7.75 inches back fron the inboard leading edge. Something else to consider are you doing your cg with the gear down or up. If you are doing it with the gear up. you will be tail heavy with the gear down. I also am running a 2oz header tank and i have that full when i check the cg

ken