I have a 2014 Model S 60. I'm looking at upgrading my car, and by upgrading, I really mean upgrade the actual car that I'm driving now, rather than getting a new car. I found a couple of salvage Model X which would cost too much to repair. However, the battery packs look good. I've got my eye on a 2017 Model X 90D. My current car is a 2014 S 60, and it doesn't look I can squeeze any more than 50kwh out of it. If I run from 100% to 0% (so not including the hidden buffer) I'm only getting around 49KWH, which really means my realistic range is only 250km / 150miles. I'm wondering if the battery pack from the Model X would fit in my Model S, and if it will, if anyone has managed to actually put in a bigger battery from another car into their own car? Before anyone advises against doing this, know that my car is already out of warranty. 1.) I've driven over 50k miles 2.) My car is now 4 years old 3.) My car is out of zone (US car in Europe) Since the wheelbase is the same, I assume the packs used between S and X and the same, and so should fit nicely. If so, then a simple software update (obviously not an OTA one) to account for the extra battery capacity, and that should do it? I figure even if the 90kwh battery pack only had a usable capacity of 743KwH, that would give me 365km of very comfortable driving, or 400km of rated range. Anyone have any experience in this area?