The line that runs across the strut tower brace comes right out of the upper intake behind the TB, so when you're under boost that portion of the tube gets loaded with boost as well. The check valve mechanism in grey should separate those things out. One line from the brake booster, one from the upper intake, and one hose goes to the intake shortly after the air filter about where it splits off to both the turbos.
ZSHO I don't believe you have the right part number. I think you need the whole assembly its about $40? I replaced mine recently and the one I received from tasca is a slightly updated design but functions the same.