Still waiting for the right combination of time, good weather, and daylight to install the harness. I'm tempted to do it sometime over the next week or two while we are visiting family but don't want to get into a situation where the car won't run
Price wise, it seems that everyone's about the same since this is a Mercedes only part. The dealer wanted $179 + tax but couldn't find one in the US so it would take over a week to come in from Germany. I ordered from *************** (actually on the phone) and got it for $190 including shipping which worked out to be about $0.25 more than the total would have been at the dealer but they had one in their warehouse and got it to me in two days.
The connections are definately all different so crossing wires is impossible. My only concern is access to all of the connections, particularly the two under the engine near the starter. I have no idea what they are for and can only guess at location right now from looking at the harness.
I'll update more when I finally get around to the install (probably on the 26th if not before).