we have been working on these quite a while and now have some samples, as the D2 has an open knuckle design we have been able to go much larger with the bell diameter from 92 to 104mm.
To reduce the stress on the inner we have increased the ball dia from 19 to 23mm.
The D2 has 24 spline at the diff and the small 32 spline at the CV, we have gone 24 spline at each end.
Bell Photos :

Stock D2 comparison with HD D2 :


Comparison of 32 spline to 24 spline shaft :

This photo shows the comparison of our existing HD CV inner with the new D2 one, please note the smaller one is almost identical (apart from the inner spline) to the HD Defender / Disco ones available in the US today from various sources,

The HD shafts and CV's will be a direct replacement for the stock ones, no mods necessary.