Good work...there is still a bit of power left there if you just bump that boost up by a couple of psi
As for the a/f reading and leak, go straight to the turbine outlet, where the down pipe is clamped on the turbine. Remove it and check for RTV. I have implemented a tongue/groove connection there, but just double check it. Add some of the red RTV that comes with the kit, and you'll be good to go.
Enjoy the car.