I need to build a level mount for the ADAHRS for the EFIS system, so I needed to reattach the tailcone to the fuselage and use the cabin deck as the level reference. I measured the angle at the stiffeners and on the bottom skin of the tailcone but in the end I ended up using the top skin as the level reference. The top skin has a slope in the aft direction of 5.6 to 5.7 degrees.
