F21-01 Fuselage Tail Cone Box.
I used my tight fit right angle drill attachment to drill four #40 pilot holes from the T12-05 Angle through the upper longerons. The box is up side down at this point so the holes went into the table top. I clecoed the four holes to the table top. I then drilled the #40 pilot holes through the side skins and the vertical fin channel. I removed the fin channel. I then had intended to use the tight fit right angle with an extension. However the tight fit right angle quit working. So I used my right angle drill with the extention to drill the remaining pilot holes for the T12-05 angle.
I then remove the lower skin. This allows access to drill pilot holes to attach the Forward and Aft Lower Mount angles to the longerons. Next I drilled the pilot hole through F23-03 Forward Lower Mount Angle where it will attach to the longerons. I used the pilot holes in the longerons from the lower skin. Then I drilled the pilot holes through F23-04 Aft Lower Mount Angle. Again I used the pilot holes in the longerons as guides. Next I drilled 1/8th inch holes in the Aft Lower Mount Angle to match the existing holes in the vertical fin channel.
I attached the vertical channel and T12-05 angle to vertical stabilizer assembly. I then located the position of the tail skid mount on the assembly and clamped it in place. Next I drilled 6 1/8th in holes through the tail skid mount using the vertical stabilizer as a guide. I clecoed the F23-04 Aft Lower Mount Angle and the Tail Skid Mount to the Vertical Stabilizer Assembly to start updrilling the bolt holes.

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