i just got the dipstick tube and used my own dipper. i had a piece of pipe made up to replace the cat so it is just a straight 2.5" pipe with lambda hole in it.(for your sensor) i didnt need to change flexi it bolted straight up to my ss exhaust.. very very raspy.. but with that and and a k&n panel and bluefin with the boot fully stripped out my speedo showed 137. on my 2.0l When i took it out for a drive.