There's someone on here that did it (k0423 on an
Ibiza), can't remember if he did any bulkhead work, but I don't think so.
His forum name was Surfer_d, I remember he sold the car to someone else who joined the forums.
I know some Porchses run bigger KKK turbos designated K24 and K26 I think, don't know which ones though. I think they form the basis of the Sportec/MTM Stage III upgrade. Not a bolt up upgrade., and not exactly cheep.