GREAT PLANES Super Sportster 90 Instruction Book page 19

3a. If the nosegear bearing is to be installed
on the back of the firewall (because a custom
engine mount is being used), you will have to
cut indentations into the front of the firewall
at the blind nut locations so the blind nuts will
be flush with the front surface of the firewall
and thus not interfere with your custom engine
mount.After cutting the indentations, install
the nosegear bearing on the back of the firewall
with the blind nuts on the front of the firewall.
4. If the nosegear bearing is on the front of the
firewall, you may now drill the hole in F-l for
your nose gear steering pushrod guide tube.
16. Trial fit the 3/8" ply firewall (F-l) so the
large notches line up exactly with the long slots
in the ply fuse doublers. Use 30-minute or 5-
minute epoxy to securely glue the firewall in
place, holding with clamps until the glue has
firmly set. NOTE: Before the glue sets, double
check to make sure F-l is properly aligned.
17. Now, using a small razor saw, cut out the
small tabs in the front of the fuse doubler at
the end of the engine mounting rail slots.
18. If you plan to use the hardwood engine
mounting rails supplied in this kit, trial fit the
rails through the openings in F-l and into the
slots in the fuse doubler. Trim or sand the open-
ings as necessary for a good fit. Glue the rails
securely in place with epoxy.
D 18a. If you plan to use an aluminum engine
mount made for your engine, do not install the
hardwood rails. Instead, glue the 3/8" x 5/8" x
1-1/8" hardwood blocks into the cutouts in F-l,
using epoxy.
19. Note that the bottom of F-l may not be
flush with the fuse sides, especially if you are
planning a 4- cycle engine installation. If this
is the case, glue a scrap of hard balsa to the
bottom edge of F-l, then sand it off flush with
the bottom edge of the fuse sides.
20. Cut pieces of 1/2" balsa triangle stock to
fit in the front corners of the fuse, above and
below the engine mounting rails. Glue in place.
D 21. Cut pieces of 3/8" balsa triangle to fit in
the rear corners of the fuel tank compartment,
above and below the engine mounting rails.
Glue in place.
D 22. In the same manner, cut and glue 3/8" balsa
triangle to fit in the front corners of F-3.
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