cheaper to do as you describe. Look up prices and you'll see that you'd have to get both housings machined for about $350, which would be hard to do on a prototype basis. .... New, the 530's are the way to go: a little more money and a much better turbo. But if you are cash strapped, Coz has brand new chra Sport 500's for a good price (I'm not pushing Coz, I just haven't seen that anywhere else.)