Light Weight Half Shafts

Hi Guys,
I have just purchased a 1974 series 3 Light weight and would like to fit free wheeling hubs to the front, I am looking at 2 different sellers on fleabay one is selling 10 spline fwh and one is selling 24 spline fwh and I am unsure which the vehicle has, can any one help me,
Many thanks

The only person in a position to find out is you. Count the fookin splines

If you've still got genuine light weight drive shafts I believe Free-wheel hubs don't fit properly anyway.