I don't normally spend much time in the R170 area but I have access to the WIS so I should be able to find what you need. I just need to know your chassis number 170/447 or 170/449? Then I need to confirm the engine 111.943 or 973? Hopefully, I can get you going in the right direction.
Thanks for the response, but I had gone so far, that I only needed to pull four bolts, and an air intake, and it came out.
What I found was there is only one port, it is a torx screw below and offset from the pulley. I saw it from the front when I removed the belt, but thought it would make a mess if I took the screw out and the old oil spilled out on the idler pulley and the serpentine belt.
Once I pulled the supercharger, and I took out the torx screw, I was all prepared to catch the "stinky" oil everyone was talking about. No oil spilled out at all since I had it standing with the rear of the SC facing down, so I slowly tilted it forward, with a towel in front of the hole, until it was level like it would be in the car.....still no oil. I slowly inverted it until it was completely face down, and finally...... a drop of oil, that was it. It was for all intents and purposes dry. I filled it, spun the pulley a few times, removed the torx screw again, and topped it off to the beginning of the threads and sealed it up. The pulley does not wobble, or have a feeling of grinding, so I hope it is OK. If not, I know how to pull it in the future.
The pictures show the engine compartment with everything out, and the picture of the components removed in the order they come out from right to left in the picture. I leaned a lot about the air and supercharging system in the process, now hopefully it all goes back together smoothly.