bjbear Good question my non expert opinion I think any location would work, I just wanted to disrupt the air in that area and trying to eliminate the cab noise. I chose to put them above the doors. Also I did not want to block the clearance light. As you know this is a******shoot no one has done it before. I will tell you I now have around 700 miles on my truck since I install them no increase in bugs and the cab noise is still min. My wife and came home last weekend into a T-storm high winds we had very little cab noise so I feel they are working. We are leaving for a two week vacation next Wed. We are heading south into bug country so I will have a report for everyone. Thanks to everyone for the support! ART