The prop is to be mounted pointing 1-2 degrees to the left and 1-2 degrees downwards. When I built it I glued in the firewall correctly, I thought.. But i turned out the cutout at the nose was cut angled and so the firewall ended up pretty straight. This gave me a yaw to the left and up when accelerating and I could never trim it correctly to have it fly straight.
You need to glue in the firewall ( with a small plywoodplate to cover the cutout for the 300 motor) angled left and down and you need to assure youre measuring from the right place.. one of the panellines in the nose instead of the nose itself. Be very careful at this and double check as it will be glued permanently and flight behaviour will depend on it
Don`t use 5min epoxy as it will cure to quickly for you to position correctly in time.
Stian