[Singleton]

Have seen a similar situation a few years ago with a friends 1971 GTO. His problem turned out to be interference between the exhaust manifold and the lower arm of the countershaft. He was using the wrong Ram Air exhaust manifolds (64-67) on his later car, and the manifold prevented the countershaft from extending all the way forward, effectively shortening the stroke of the clutch pedal. I ended up grinding a small relief in the manifold to allow slightly more travel. So make sure that nothing is preventing the full forward pivot, (or starting point of clutch travel). You have a completely different car and exhaust, but thought I would throw this example out there.