I received this H pipe for christmas as my wish list was pretty much a build list for my Mach 1. The install was super easy, about 1.5 Hrs on a lift. This is the second one I have installed, the first one was done with floor jacks and jack stands in my garage on an 01 cobra with bassani Exhaust. The cobra took 2.5hrs since it was a little less accesible than on a lift. Both installs went smooth with no leaks or squeaks and the only problem I ran into was scraping just a little bit since my car is lowered and my driveway is as steep as a mountain. Neither car required MIL eliminators but my 04 Mach 1 did require the use of o2 extensions, no big deal. The pipe sounds awesome with my flowmaster 40 series weld-ins. I would recommend this pipe to anyone with a 99-04 mustang.It makes your car sound and feel like a whole new car! Price = 5 stars Ease of install = 5 stars Fit and finish = 5 stars Sound = 10 stars!!!!!!