F21-01 Fuselage Tail Cone Box.
I positioned the Aft Shear Web Assembly and drilled #40 Pilot holes through the longerons. I also drilled a few of the #40 pilot holes through the aft angle using the bulkhead for reference. Next I clamped the forward Angle F22-06 to the channels with it tight against the shear web and the channels. I drilled the holes into the channels using a long 12" 1/8th bit. I used the tight fit long extension to drill down through the angle and shear web. I clecoed it all in place.
Next I debured, Cleaned and riveted lower cross ties #5 to #1 one at a time.
Next I put the Lower Skin back on the box with clecos. I then up drilled all the holes to #30 size. I also up drilled to 3/16th the 2 holes that will get bolts for Forward Lower Mount Angle.

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