Joe,the inverted double "u" is a great idea.If I use this ,I believe I would insure that the single screw is well anchored,and the attachment block is solid.The roller portion has slots in the attachment.I am not sure tightening the screws will prevent slipping.I can make the fit tight enough with a single inverted "u"that the roller bracket will move.
The advantage of the double would be that the grip could be the same,but the force needed to release would be doubled.
Harvey
The advantage of the double would be that the grip could be the same,but the force needed to release would be doubled.
Harvey
