Just sat down after replacing the CPS on my 2004 X-fire. Don't know if it will fix my hot start and stall problem but the soldering of the ECM as prescribed did not. In any case, as with most DIY auto projects, the job is eased a great deal by possession of the correct tools. The sensor is located in what I would call the bell housing behind or protected by a metal shield. The removal of the plug is easy once you grasp the fact that you need to locate the tab locking it in and press the portion closest to you as you grasp the plug and pull it out (cool engine is recommended for those without teflon hands).

Now, as described by many, the bolt holding the sensor in place is a spline bolt and I had to purchase a set of spline sockets (AutoZone $14.95). The size is 1/4". The only set I could find was for a 1/4" ratchet which does not fit into the small space between the bolt - the metal shield - and the CPS body. I decided to remove the metal shield (7/16" socket from my new purchase) which made access much easier. When removing the shield, there are two large spline bolts. Go around to the passenger side to reach the one farthest from the CPS. The bolts are long so do not worry if you are ratcheting for a while.

BTW, the CPS was purchased at AutoZone for $61. Part #CSS825.