E-flite DHC-2 Beaver 25e ARF - Manual (Page 31)

31 E-flite DHC-2 Beaver ARF Assembly Manual
 12. Use a sharp hobby knife to cut the covering
slightly below the lines drawn. Be very careful not to
cut into the underlying wood, as this will weaken the fin
and cause it to fail in flight. Also trim the covering on
the top of the fuselage.
 13. Check that the fin is square to the stabilizer. Sanding
the bottom of the fin where it fits into the fuselage can
correct for any alignment issues. A slight amount of
material from the bottom of the fin might need to be
removed for a correct fit.