I'm starting a new thread since there was one where this product had been discussed and at least one member wanted to see it installed. Here is it in my '98 E300. It took about 15 minutes to install. It's stuck using heavy duty stickum tape to the top of the little shelf which protrudes over the steering column extender but that piece does not move so the steering wheel adjustments can still be made.
I just pulled the lower panel down (3 screws removed to get it loose) and tucked the wire in behind that panel and came through an existing hole at the bottom where I zip tied it in place. I removed the door to the OBD cover though I could have left it flopping there. If you are careful you can remove the door without breaking it...I broke mine