Even the best of the line drawings you can find take days to justify the sections to the plan and profile. The I go to "airliners.net for as many photos that will help me see the true shape. The stuff I got for the Beechcraft 350i King Air I am finishing up had sections that were very round. But found some fore and aft end view that showed the sides bottom and top were not so round the had almost the same radii on the corners front to back!