radhaz

I just did mine, here's some observations:
It appeared to be the original (or at least very old) and was stuck in there pretty good. Lots of wiggling and pulling in a very confined space. I have small hands, and getting in there was still a bear.
The best way to do this is remove the clip that holds the sensor, pull the sensor, undo the connector (small flat blade screwdriver, if you hold the sensor so that you can see into the connector, you'll see the locking tab) connect your new Chinese sensor with new o-ring, and insert it back into the pipe. It is pretty tough to get seated. I used a large flat blade screw driver to press it in. I also checked that it was fully seated by using an inspection mirror and flashlight. You can just see the green connector body through the clip slots if the sensor is seated.
Hope this helps~