the tee in between the high pressure line that goes to you wastegate. then one end of the flow control valve goes to the tee and the other bleeds air to atmosphere. once you install the boost controller you will notice that your min boost is no 15 psi rather than 10 psi
the actuator side is metal but closer to the turbo should be rubber
You should still be able to install it, just don't vent it inside as oily air may come out the tube.