I am planning on installing a boost gauge on my 2006 WRX soon so I have been watching a lot of videos and reading up on the installation procedures. When I went to take a look at the vacuum line, I noticed it had already been cut and a t-fitting was installed. The hose from the fitting is sealed by some metal plug. I am assuming the previous owner had installed a boost gauge and left some of the equipment instead of buying a new line. My question: Should I leave the plastic fitting or install a brass t-fitting? I have heard some of the plastic ones are pretty crappy. Also, is this the most common/best place to install the t-fitting? Thanks in advance!