I need my yearly therapy. I'd like to rebuild a 300CD. I'm wary of the Turbo. As an amateur, I dont think I would rebuild the Turbo, because Turbo clearances make me nervous. Or else is it possible to rebuild ? I did a 240D no turbo 4cyl rebuild last year. or would I have to replace a shot one? How do I evaluate the condition of one on a car I'm buying, and what is thier approximate longevity on a well maintained car? Could i buy one and just leave it alone?