Figured I would jump on here, since this is the "Follow up" with Jimmyb's build... and my what a thread it is... you have quite a bit going on...
To follow back up... I am curious about the status of the wastegate... did you leave it capped off, did you find an aftermarket wastegate actuator and install that? The boost valve seems more and more like a cheap, not all that effective work around to a turbo pushing weak boost. If we have a decent tune and an open exhaust, do we need a wastegate on such a small turbo that is flowing exhaust gasses freely? capping of the vacuum line at the intake side of the turbo would certainly be the easiest fix to the weak boost.
I don't know what pressure this turbo is capable of producing from our motors, but if we are runinng stock pressure and with the valve hoping to increase it 5 PSI to 12 maybe 14 if lucky... does that really require a wastegate? Not like a 25 - 50PSI boost pressure from a bigger turbo.
Forgive me, i have a tendency to ramble, i am curious though.