Doron Swade who wrote "The Difference Engine" (the non-fiction book, not the steampunk fiction by Gibson and Sterling) can tell you this:
It's not possible to create The Analytical Engine. Why? Because Babbage never stopped creating the designs. There is no one clean, complete set of designs for the Analytical Engine.
If someone were to build it, they would first have to pick and choose from among Babbage's numerous sketches, then fill in any of the missing bits. It's not a true, 100% authentic, Babbage design, unlike the simpler Difference Engine, which had a clean set of engineering drawings for its creation.