The shop in Cincinnati is Fisher Griffin. I have not yet contacted European Connection. I will do that today or tomorrow. I plan to visit Fisher Griffin tomorrow and get the full scoop on the installation. The guy at Berg Werks made it sound like it was no big deal to install them, he's the one who led me down this path after it was suggested that I contact him on this thread (thankyou very much Mattman).
There are two different ways to do it.
1. The factory way which is to install the heater switches into the console, the wireing harness etc...expensive @ $1,000 per seat was quoted over the phone at the local MB dealer.
2. Aftermarket way which is to install the heater switches into the plastic cover at the bottom left side of the drivers seat (right side for passenger.)
It is also easier on my W140 to draw power from the rear fuse box instead of the front one. there are several open fuse slots (one for a refrigerator in mine) that have adaquate power for the heaters.
This is where my research so far has led me so far. I have not yet made a decision. I'll keep you posted