spit differentials

[William Hartwell Woodruff <woodruff@engin.umich.edu>]

        A friend of mine is rebuilding a spitfire differential.  To
determine to correct amount of shims to use when replacing the pinion
and pinion shaft, you need to make some measurements using special tool
%$^#$!!.  From the pictures in the Bently manual, it looks like a dummy
pinion shaft - except being a little longer.  Does anyone have experience 
doing this or know how to avoid it?

woodruff@caen.engin.umich.edu