I got the right side mirror and mounted it on the left under the bar. Don't know if mounting the left upside down would be any different due to mounting bracket. Mount it firmly on the bar then snug the mirror ball up gently a bit at a time without over-tightening the little guy. Good for it to be able to move without breaking if it gets bumped but not move over rough terrain, like the mirror in your car. Good luck if you go with it.