Just finishes my Mach II this weekend. My plane turned out to be extremely tail heavy. I put a OS LA 46 on the front and didn't change anything but the hold down bolts to nylon. One of the T-nuts was hard to start. Didn't think in time to move the battery under the tank. Tank all ready installed. As light as the plane is I wouldn't have though it would turned out tail heavy. Any other builders had this problem with their plane. Need suggestions. I have added about 5oz. to the nose just to test. Seems to make it about neutral. Need help!!!