How much did it cost to install your cat-backs
$0 + a couple cans of soda. I installed my self with a friend, The only hard part is taking the old one off. I had to borrow a hack saw because I don't have one once I cut it in half it came right out. Putting the other one in was ridiculously easy. I don't have any leaks that I could tell.
Yeah, a catback should bolt right in. Just pull up on ramps, jack the rear up and put on jackstands. Cut the I-pipe near the axle and remove old exhaust. New exhaust bolts right up. No $$ needed for muffler shop. If you end up with a small leak you can't seal up then maybe you need a shop to weld that joint but it should only cost $20-40. Sounds like we need to start doing some "how to mod your car" seminars! 
$50 to remove the old catback and put on the Magnaflow at a local muffler shop and I was a ***** and made him put it back on the lift so I could adjust the tips exactly where I wanted them before he clamped them down. He was cool about it.
