4.2 a6

So it's coming down to the wire and i have to decide on a pre owned a6. I'm considering price, mantaince, power, and insurance. So.... the 2.7 is always fun to drive, ok on gas, and turbo charged, its the perfect 4door sports car, that doesn't look nor sound like one. But then i had a dangerous Idea, what if I get the 2000-2001 4.2 a6 and save up and throw in the RS6 Turbos? I know the turbos them selves would run about 5 or 6k but have any of you tried it or know anything about, any other mods i would have to make to have a 450hp a6