I'm designing a dolly for a backhoe on a new B2650. I've seen enough videos/photos to understand the basic design but here's my question: how high should the rear of the dolly be compared to the bottom of the backhoe as it sits on the tractor? Should the dolly just sneak under the backhoe with as little clearance as possible, or doesn't it matter? How much clearance would be too much clearance? Does it make much difference whether it's 1/2" or 2", for example? Thanks.