[The Troll]

Okay I'm Serious Now. Have you tried putting a 6 inch metal plate in the middle of the wheels. If cut right and wielded it will not hit the corners purtruding out. It will connect to the rotational device. When it spins it will hold it in place while still being able to move with reinforced steel to back it up. I hope that helps. Make sure it's small enough so you dont have it flopping like a fish.