Here's a view of an ABZ (32 valve cable throttle Audi V8) as I was figuring out my subframe cradle:
My positioning is based on mounting the transmission to the engine, then mounting the transmission normally in the car.
The 40 valve, electronic-throttle engines fit about the same.
The Audi motronic 7.1.1 ECUs are pretty easy to reflash (for the 40 valve engines), but so far I have not found a good version (freely available) for the manual transmission on the A8 ECU. The info needed to create it is available through NefMoto and as I get my engine running in the Boxster, I'll figure out exactly what changes need to be made.