FR-64S Advanced Nullpoints


Hi everybody,
I searched the threads but the main data seemed to be missing.
If i use the mounting distance of 231.5mm and the overhang of 14mm as DerTonarm proposes, according to which calculus should i seek the nullpoints? Loefgren A was said to be good for 9" but not optimum for the 64S. Is it Stevenson or are there distinct nullpoints (like Allen Wright's Guru Protractor)?
Thanks for help.
difool