Installation went like every set of headers that I have installed in my automotive life. By that I mean that exhaust pipe bending and replacement was required. As I am 68 years old, it is unlikely that I will ever install another set of headers in my life. I have never installed a set that did NOT require major work by the muffler shop to complete the installation. However, they addressed the performance problem I was seeking to correct. The unexpected benefit was a quieter exhaust.