Why not? Look at what mankind already has done when properly inspired. Mount Rushmore. The Goldengate Bridge. The various building known as The World Trade Center. La Sa Grande Familia. The space shuttle. Men on the moon.If there's anything the art, architecture and science of this world shows is that there is NOTHING we can't do if we really wanted to. A person can draw one of these on paper, therefore a team of people CAN draw one in a corn field. We lay down symetrical buildings bigger than these things all the time, and they're in 3D and need to have loads and strengths calculated. The only question is can it be done overnight without being caught. And anybody that's watched a multifunction stadium be converted knows that if you throw enough trained people at a problem it can be done in less than an hour. So that leaves the only question as can it be done without getting caught.