For anyone looking for an Audi V8 powered Boxster, I'm selling mine as I am headed overseas.
http://986forum.com/forums/boxsters-cayman-cars-sale-wanted/82568-2003-boxster-s-audi-v8-engine.html#post648877
Priced to sell, have at least $45k into this without my time being accounted for. Half what it would cost you to build yourself.
My loss is your gain - would love to see this car go somewhere it will be raced in anger.