I installed the 2" ceramic coated headers with 3" X pipe exhaust on my 72 Roadrunner with a 4 speed. Fit is awesome. I am running the Indy Cylinder Heads "SR" heads and a mini starter. If I remember correctly I did have to trim the X pipe length like 3". Make sure you follow TTI's recommendation (coating headers with WD40) when storing your car for an extended amount of time.