79-81 mustangs do not have a clutch quadrant, they have a straight metal bar with a pin on the side of it where the quadrant would be on an 82+ stang. The cable connects to this pin and the cable comes with a firewall adjuster and is only $25. This doesn't help you in any way its just an FYI since most people have no idea about this.
Im kind of supprised people dont convert to the 79-81 style, cheaper cable with an adjuster, petal efforts not increased much. The only down downfall is its not self adjusting.