There are 2 things I would try to get in balance.
1. Try a 1 ounce prop nut. If you are close, it should bring you in tolerance.
2. If necessary, add weight to the nose to the left and right of the engine. Be sure to epoxy it in place when you have determined the proper amount. If you need more than 2 ounces, consider moving the landing gear forward a bit.

Good Luck
Mike