When you pull the passenger side wheel (use a jack stand) you will find an opening at the rear of the wheel well. You will need to reach forward and feel for the sensor. a 22mm open end wrench is just what you need to loosen the sensor (after disconnecting the wire connector on the fire wall.
I was able to (with some effort) unscrew the sensor with my fingers. Just reverse the process with the new sensor after applying some anti-seize to the threads.
The passenger side took me 2 hours the first time and about 45 minutes the second time (I used cheap sensors the first time). The driver's side is easy using a sensor socket (offset type).
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