Outback cart post bushings

I just got my scupper cart for the Outback, and it came with clamp on cart post bushings. They didn't work as in too fat to contact the scuppers. I searched on the Hobie forums and found that using tennis balls, slid over the posts to take up the slack, seem to work. Has anyone here used this method and had luck with it?

It does work....you can add a pool heavy duty noodle across the horizontal bar too.