I'm an American currently living in Germany and have a 1999 A6 1.9 TDI. It won't be old enough to take home, but I know if I take the engine,ECU, drivetrain...etc, I can ship all parts with my household items. My question is for anyone, esp if in the states, who has converted to a diesel. How difficult is it and what modifications do I need to do if any? Or is it just a simple remove and replace. Is there another model I can use other than another 1999 A6?My car is perfectly running fine with no problems and would love to have it back in the states. Thanks for any help/advice!