I have mine rotated backwards to accomdate the light bar, loks cool that way and it did make a difference in airflow. I didn't want lowers but they made enough of a difference that I kept them on.

I have the mounts for the uppers. But I do think that the lower mounts do make a difference too.

I have not tried this option yet but one of the members mounted teh lowers via one of the lower windshield mounts by removing a spacer.

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