E-flite Brio 10 ARF - Manual (Page 24)

 4. Measure from the stab tip to the wing tip. Adjust
the stab until the measurements are equal.
A A
A=A
 3. Position the stabilizer into the slot in
the aft end of the fuselage. Slide the stabilizer
as far forward as possible. Center the stabilizer
in the slot in the fuselage.
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