You seem knowledgeable and i cant figure this forum stuff. So if you have a minute. I have an 04 5.7 I am buying pacesetters, and the magnaflow dual out exhaust. im trying to figure out the y-pipe and catalytic conveter connections. magnaflow told me i only needed part number 93402 or 93403 along with the exhaust system 15863 id like to see something togethre. any ideas would be helpful. thanks