to keep it from bouncing why not wrap the area to be clamped down with some electrical tape.
if there is a possibility of stripping the screw from the aluminum you can use steel strips on each side and use a nut and a bolt that way you are applying torque to the steel strip and not the soft aluminum?
just an idea.
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'00 Dakar Bus CRS Edition
LCD Squad #0001
Originally Posted by WiLL
...I really wanna get out and shoot people.