It wont work. I don't have to explain it you zax. I know, you know.
116fanatic: To swap an STi tranny into a WRX would require different driveshafts, differential, half shafts and shift linkage, etc, etc. Basically the entire drive line after the tranny. At that point you'd be getting close to the the price difference of an STi. Unless you're making an USDM STi wagon, that would be sweet.