Hey guys I've read and tried to search through the current threads about cat deletes but didnt really find one with the specifics i need. This weekend I'm thinking about taking my car to a friends shop and creating a straight midpipe thats bolt on. My question, now from what i've seen my car is a S5 or 91' and the air pump supplies the needed air to my aux ports. What all should I expect when removing the stock primary cat and junk midpipe? I've been under the car once as it's so low its sketchy as can be when its hovering on two jacks and i've seen a pipe running to my cat, what do i do with this?