There is a two-piece plastic beauty cover. The rear view mirror is held up with a screwed in 6-point head like aT-20. Mine was loose!
After that you'll see how radar sensor hooks onto the windshield and rain sensor sits below it, if so equipped. The rain sensor is just a little puck that has a radar sensor that monitors for water droplets. No need to remove it. I did not disconnect any sensor, just worked around them.
On my Cadillac XTS is helped the rain sensor be more reactive but it is a different style of sensor.
2016 Envision Prem ll