I'm thinking about changing my gear ratio and have a couple of questions. I have a 2010 coupe 3.8 Track, manual. To go to a 3.9, what can I swap internally so that I can keep the lsd? And will a 2010 2.0t with the automatic transmission be a suitable donor? It's final drive is 3.9, but it doesn't have a 6th gear. Or do I have to find a 2.0t donor that is manual with lsd, and swap the whole differential?