Uncle Henry: Here is the reply i got from Turbo Calcuator about internal wastegates on GT30 turbos. Or anyone else thats interested:

We can probably swap on a housing with an internal wastegate on it for you.
This will require some modifications, however. What housing would you like?
We have 0.48 A/R and 0.63 A/R. I'll look into it and get you a price, but the 0.63 A/R housing will be $130 more than the 0.48 A/R housing.