I drove down to Aircraft Spruce EU in Bretten,Germany, about an hour and a half from my house, to pick up 28′ of 1/8″ 3003-0 aluminum tubing for my brake lines.  I also picked up some Alodine, a 3′ hinge and a plastic eyeball vent.

When I returned to the house, I finished the other 3 angled aluminum seatbelt brackets and final-drilled all the holes to 1/4″.

I then lined up and drilled the seatbelt bracket mounting holes into the corners of the fuselage at each of the 4 seatbelt 7-ply BID/1/4″ plywood hard points.  Note that in the pics below that the screws are simply inserted into both the seatbelt bracket and hardpoint holes for spacing purposes only, since the screws are installed backwards—as you can tell by the screw head being on the inside of the fuselage vs. the outside.