People often mount to either side of the sensor box on windscreen, some have also mounted off that sensor housing if it have a flat surface in the fight place to do that.
Just have to make sure you have a little room so the camera can slide on off its mount, not least if you go for a wedge shaped camera like viofo / street guardian / ASO
Also need some distance so you dont have parts of that sensor housing in the footage.
I know the best place to typically place these cams is in the center usually behind the mirror. Problem is my car has a lane keep system located behind the mirror, kind of like in this image http://cdn0.mos.techradar.futurecdn.net/art/car tech/2017 Ford Fusion/2017 Ford Fusion mirror-420-90.jpg...