I have a 1995 Audi S6, bought as a winter car, long trip cruiser. Has the 2.2L Turbo Inline 5-cylinder, manual 5-speed trans and locking rear diff. Unfortunately the fuel tank started leaking this fall, and of course, right after replacing both front CV shafts, and brake rotors. So I am not trying to decide what to do with the car.
Replacing the fuel tank was the easiest answer, but... to remove the fuel tank the entire exhaust, and rear suspension/sub-frame has to be dropped. But the biggest problem is that I can not find a replacement tank, there isn't an aftermarket stock replacement.
I've looked at fuel cells, and the trunk is pretty large, but won't be very usable with a fuel cell in the middle, or even tucked into a corner.
So I have kicked around the idea of parting it out, an AWD 5-cylinder drivetrain should be useful to someone. Or I could strip it down, and do some rally-x. We have been trying to thin the herd of cars we have though, so finding it a home would probably be best.