17
❏
2. Drill 1/16" [1.6 mm] pilot holes through the “
+
” marks.
Then, enlarge the holes with a 3/16" [ 5 mm] drill.
❏
3. Press M4 blind nuts into the holes in the back of
the firewall.
❏
4. Temporarily fasten the engine mounts to your engine
with a M3 x 25 SHCS (with M3 lock washers and fl at washers)
through the
front
holes in the engine mount lugs and the
rear
,
elongated
holes in the engine mounts. Do not tighten
the nuts all the way.
❏
5. Temporarily mount the engine mount with engine to
the fi rewall with four M4 x 25 Phillips screws and M4 lock
washers and fl at washers. Use a Great Planes Dead-Center
hole locator to mark the rear engine mount screw holes onto
the engine mount.
❏
6. Before removing the engine from the mount to drill the
rear two mounting screw holes,
sight-down
a location on
the fi rewall for the throttle pushrod and guide tube. There
is already another “+” mark for the O.S. .46, but if using a
different engine you may have to mark the hole in another
location on the fi rewall. Be certain the hole will not interfere
with the blind nuts for the engine mount bolts or with the
fuel tank once installed.