If using headers with the install, buy a set of the aluminum gaskets for this joint so if there is the slightest angle difference they still seal well. TTI's are good but not as good as the maelable aluminum ones. Use a light smear of high temp (red) silicon on all slip joints and on the joint bands. If you're using the 2 1/2 inch system especially, because they condense a lot of water inside and then the drips of black water on the garage floor will drive you crazy after the car sits. Don't trust the sealing strips on the band clamps. Be aware of the clearance between the mufflers and the drive shaft especially once the car is set back down on the wheels. Install from the front back connecting the header flange and tightening first being careful not to side stress this joint with the rest of the installation and mind that cross-over slip joint that is a bit difficult to set for the exact width between the left and right pipes. They both have to come in evenly and together at this slip joint or one side of the exhaust will have tension. Not good when they heat up and expand slightly.