I'm hoping there is someone here who has completed what I am attempting successfully, so here goes... I have a December 2014 S85 with Gen 1 seats. These have been the one biggest drawback to the car. I didn't react quickly during the brief period that Tesla would have retrofitted Next Gen seats into my car, and the $6,000+ price tag was also a turn off. I recently purchased a set of black Next Gen seats in great condition, and set out on my mission of acquiring real driving comfort. I read all I could find on the topic, and reached out to several members for input. Pulling the driver's seat out of the car, I immediately noticed the electrical connectors on my car and the seat were incompatible. Turns out the seat was made toward the end of 2016, and nothing was the same. Looking at the passenger seat, however, I saw this was a March 2015 build. I pulled the passenger seat, and it was an easy swap. Controls all work, but I'm only halfway there. Even though the seats are from different years, they look identical, and shame on me for not catching the difference when I bought them. Here is where I've hit a roadblock. I'm being told by some that I have to switch out the wiring harnesses. If you've ever looked under the driver's seat of a 2014, there are two 12-wire connectors and a three-wire airbag connection. Once into the seat, the harnesses diverge greatly, going all over the place. Into the side seat controls, the seat belt buckle, the Memory Control Module, and other places. The way the cables are buried inside the metal seat frame makes me very nervous about successfully removing and replacing them without buggering something up. On the 2016, it is a 8-wire connector and a 17-wire one. Since I don't have access to the wiring diagram for the seats, I'm looking to see if anyone has done this: Cut off the two large connectors from both seats, then resolder into the opposite seats. Do the same with the airbag wires. The wires all seem to match up, although there are two yellow wires in each pair of connectors. Also, the 2016 has one additional wire the 2014 does not have. (I've heard that this could be for the movable headrest in the Premium seat, but these are not Premium, so I don't know). I'm really trying to get this done before I drive to San Diego this weekend. My wife will have the comfort of the Next Gen seat on the passenger side, but I'd really like the same for me. (I know about the door panel tethers and PRSCM reprogramming.) I'm really trying to determine if all the wires are still doing the same functions. I don't want to do this, turn the car on and have something go 'pffft'. Any help will be greatly appreciated.