Stabilizer installation:
Cut free the trailing edge of the vertical rudder in line with the stabiliser, in
order to allow you to slide the stabiliser into the fuselage. Keep the
removed section for later.
Trial fit the stabiliser into the fuselage. Make sure that it is centered
(measure the tip of the stabiliser to the tip of the wing on both sides and
make sure they are the same distance) and correctly aligned (looking at
wings and stabiliser, should show all being parallel)
Once centred and aligned, mark where it meets the fuselage. Remove
the stabiliser and carefully cut the covering on the inside of your mark, for
gluing.
Prepare a mix of Epoxy and generously coat the inside of the fuselage
where the stabiliser will fit, then re-insert the stabiliser into its final location,
checking again that it is centred and aligned.
Glue back into place the section removed earlier in this process.
Excess epoxy glue can be removed with acetone