OK.

Some instructions

- move your rear view mirror up and out of the way (as much as you can)
- split the windshield mount in two halfs (you can try a finger nail or a plastic panel removing tool)
- disconnect electrical connector from the sensor

this is where it gets deep. I would suggest you split the new sensor into two halfs. The glue and front part and electronics back half. You will notice how the two parts are connected. I would do this as I found it very difficult to pull my old sensor off the windshield. (In my case I used needle nose pliers and pulled a little at each time. It took me a good 10 minutes)

on the new sensor
- separate front from back of the senor

on mounted old sensor
- pull two metal tabs outwards (to release from windshield mount)
- using thin screwdriver separate two parts of the sensor leaving the glued part attached to the windshield
- align and snap the new electronics part to the window mounted half
- connect connector
- reinstall two half left and right side of the mirror post

IMPORTANT
- at no time do you want to exert outwards pressure on the windshield that is of great force. You make a spider web crack: you gonna have a bad day.

Good luck and let me know in case I was not clear in my description.