Okay, yesterday me and buddy installed long tube stainless works headers on his 2016 Mustang GT. He already had a Borla Attak cat back on his car. When we put the headers on the car the mid pipe and x pipe where where not completely lining up (maybe a 1/4 to 5/16ths of an inch off) when we hung the exhaust. So we put the driver side together then pulled the passenger side mid-pipe towards the x pipe and put the clamp on it (pushing the end pipes to center). Used some Aluminum silicone on the clamp and bolted her up. We have no exhaust leaks that's good. Everything appears close to centered as far as exhaust tips and what not. However, when we went on a test ride after the install we had some slight vibration in the gas pedal between 2-4.5 hundred RPMS seem to have a weird rumble on left hand turns as well. You can barely hear the rumble and just slightly feel it. Car is tuned for the long tubes. The rumble comes and goes. Went over some rougher roads and could not hear any clunking noises that would indicate anything was hitting the bottom of the car. Performance does not seem to suffer. Car has 54,000 miles on it.