For those of you who attempt to replace the transmisson sensor housing, may I offer a small tip to save frustration. I had purchased the new part (they no longer sell only the "o" rings) in anticipation of my SRT6 developing the trans leak. Instead, I needed the part first for my 300C (same transmission). It would leak a few drops when driven on a very short trip in colder weather: I guess the transmission never got warm enough to swell the "o" rings. Anyway the part change was pretty straightforward, and I only lost about 1oz.of fluid, having jacked the car up pretty high on the passenger side only. When I tried to insert the new sensor guide, it would not seat, and I could not engage the 7mm bolt. I checked the guide slots (they were correct), but the new black "o" rings are much thicker than the old white originals. After about 30 minutes of absolute frustration and futile pushing on the part, I took a deep spark plug socket which spanned the 7mm bolt and rested on the plastic ridge above the pins that go through the sensor guide and gave it a light tap. The part snapped in, the bolt engaged, replugged the sensor, and I was done. It should have been a 15 minute job, and it will be when the SRT6 needs the same repair.