I bought what I assume is the unit you refer to. I set it up on temporary brackets to test it out before drilling any holes. I didn't think it was working all that well. There were spaces in the coverage area behind the truck. I figured it might be because there are only 2 sensors in the kit. Most of the factory units have 4, 5 , or even 6. Even the licence frame type I've seen has 4 sensors on it.
I tossed the kit in a drawer, thinking I might someday try it again. I haven't yet.
Dan