I wrapped from bottom to top. I started making my wrap by drawing a line through the center of a 4x8 sheet aluminum. I then hung it from ceiling under the belly of the fuselage. I aligned the line that I had drawn on the aluminum sheet with the previously drilled holes in the stiffener that runs on the bottom from Bulkhead C to D. When I could see the black line, through the holes, I then drilled and cleco'd along the stiffener. This is how I started the wrap.