Quickie Q2 Lite Construction Manual - page 229
Previously, you have mounted the attachments for the shoulder harness in
the main wing. In this section, you will install the mounts for the
seatbelts, and, finally, install the seatbelts in your aircraft. Do all
of the procedures exactly like these plans state; this section is your
first line of defense in the event of a mishap.
.....
The seatbelt mounts are installed in the fuselage between the aft
edge of the fuel tank and the forward edge of the seatback bulkhead.
There is one outboard seatbelt attachment on each side of the cockpit,
and a double seatbelt attachment of BLOO.
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The outboard seatbelt attachment is straight forward and
illustrated herein. A piece of 1/4" plywood about 2.2" x 1.2" is sanded
to fit the fuselage contour and beveled for the lamination of 7 BID over
it; between the plywood and the fuselage skin use epoxy. The 0.7" MIN
overlap onto the fuselage is very important, as is making sure that the
glass does not turn any sharp corners. The two holes for the AN525-
416R14 screws may be drilled from the inside of the fuselage all the way
through to the outside; the holes for the screws can be filled with dry
micro later. The aluminum angle should be about 1.2511 in length, and
permit at least 3/811 from the center of each hole to the outside edge.
The angle should be installed permanently, and then the hole for the
AN4-5A bolt holding the seatbelt itself drilled afterwards, so that the
hardware does not interfere. Note that the seatbelt pulls off at about a
45 degree angle. You may wish to sit in the aircraft and pick the
optimum FS for the seatbelt fittings prior to bonding the plywood in
place. The other side is a mirror image of the one illustrated.