[FrostZ]

The driver side AUX rad on the driver side is actually a secondary intercooler for the supercharger coolant, which unfortunately opens that can of worms. You have two options, one you can make a new line that runs from the source of the upper line, I cannot recall if it is the intercooler pump or the blower right now, and take that to the inlet of the front intercooler. This is how the lines run with the aux rad in the middle, or you can just get a dual male barb and take the two hose ends of the formed OEM tubing and put them together, which is what I chose to do. Either way you are opening the "vacuum sealed' factory intercooler loop. Any air in the system will cause the intercooler pump to cavitate and shutdown for a few minutes before it will try again, even with the car running you won't get any warning the pump has shutdown. I chose to install a supercharger coolant reservoir in the past that made this concern moot in my case but this must be taken into account if you are running a full OEM loop as of now. You could install a reservoir, have the lines purged using some online methods, or have a dealer vacuum fill it for you. I've decided that the one time purchase and simple install of the reservoir removes any chance of air entering the system in the future and never needing to work through the gravity or vacuum fill process to be worth it. In the case of the oil lines near the cat, I deemed mine to be far enough away that shielding was unnecessary but it couldn't hurt if done properly to avoid rubbing anywhere.