As I understand it backstage gates will block Pixar Place roughly where the sign arch is today. Once past the existing bathrooms on the left you'll continue along the existing pathway, crossing the backstage road running currently along the back of TSMM. Sets of gates will block this road on either side during park hours. Passing a DVC kiosk the path will curve left, with the coaster in front and to your right.
Theme wise I'd expect it to be smart generic up to the backstage road crossing.
The 1989 tour bridge will be gone, and the plans were for Stage Four (Narnia/Pirates) to be removed too though IMHO it wouldn't need to go. There's plenty of room between the buildings, again IMHO.