Interesting choice on the Audi motor! I'll definitely keep an eye on this thread as I am about to do my first conversion using a Renegade kit but if you come up with a better solution I'd be interested to learn more about it!
I decided to go with a GM crate motor and total conversion cost is about $16K right now not including the car, just posted an introduction here:
BoxsterLS376 introduction - LS3 conversion :)
Good luck!
J