Fabricated formed angle stiffeners for the last and second last compartment belly skins. These prevent 'oil canning' of the aft floor areas and reduce noise during taxi.
I fluted the formed 0.032" angle to remove slight bows (or the 0.025" skin would take on the bow). I then turned the fuselage over to locate the end holes, deburred, dimpled and primed. The other holes need to be drilled from the inside (or they wouldn't line up).