14 mm is only about 9/16 of an inch. That doesn't sound right to me, unless the wing is highly swept back and the measurement is taken at the wing tips. It's possible that they meant 14 cm all along and the mm was a misprint.
If 14 cm back from the leading edge is about 30% of the mean aerodynamic chord (MAC) then that's what I would balance for.
The leading edge of this plane is swept back a little so it is also very important to find where to measure this, near the fuselage or at the wing tips?