Flying Room Project: Building the Room

This is the room that will be "flying", er, asymetrically rotating suspended from a truss. The room is 700 lbs by itself, and 1300 lbs with performers and finished interior. The completed room/truss/counterweight is 2500 lbs, or 1.25 tons. How do you safely suspend 1.25 tons? With a 2 ton gantry: