If your turbo housing has a double flapper instead of the updated single flapper it is a stock evo 8 9.8 instead of a updated 10.5 and will not work with and evo 9 turbo. this is what I assume, and of course why would you want to use a 03 or 04 housing that is only a 9.8.

 

there are 10.5 housings out there with double flappers. One account is the TME turbo. It has a 10.5 w/ double flappers. Your assumption is correct for the US market though.