You wont listen to me becuase me reputation is fucked. But for what it is worth dont go too nuts on high flowing the ct26.
GCG turbos did my 2nd turbo after it blew and made it too big. I wasnt expecting them to repair it like they did. I was really disapointed with its performance. It was useless untill nearly 5000RPM.
I took it off and replaced it with the current, slightly modified turbo and i am v happy with it. Garret put it together for me using their internals. They only reused my housing.
If you want to me to get its specs i will (if you listen to me, which i doubt.)