Sweet, that’ll be a 3-port then, almost all of the factory plumbing gets ditched when you do that.
Shouldn't be going to the BPV. Should go forwards under the manifold with the turbo inlet pipe to the factory solenoid, and then from there to a port on that inlet pipe.
Hard to say why it's boosting differently without seeing how it's plumbed up after that tee. How high is it actually boosting?
Could just be a restrictor pill in a line somewhere that isn't right for the new turbo but seems unlikely. Since it all gets ditched I wouldn't worry too much and just try keep boost down and check everything is tight in the mean time