Bob and Jean Webb

    the series 5 had the 7 1/2 inch clutch. early clutches were coarse spline and late production had the fine spline. not all fastbacks had the 8 1/2 inch clutch. my white car is a low mileage car with the same 7 1/2 inch, fine spline clutch as the late series 5. I have car number 711 and 944 and both have 7 1/2 inch clutches. tear it down first to see what you have.