Hi Vic
Cant find any pics at the mo. there here some where......The belts are basically mounted each side and conected will a bar, the same setup as if you where going to use belts for the main drive. The belts work indipendently of the ballscrew and just control the racking. If the ball screw is in the middle and your aiming for 800mm O/A width then it might be worth trying with out it (only 400mm each side)

If youve got ACAD Inventor why dont you you run a FEA test for stesses, Im trying to get my hands on that program so I can do the same. Ive got Vannilla cad at the momment.