I think for the 2 bearing spindle the two bearings are identical. How about the D=-4 and d=-2 which I assume are OD and ID offsets in microns. Did you just "get" these values or did you ask for them?
No, the back bearing is definitely smaller than the front - think it may have been a 7205, same P4 class.
Little bit late responding and I see the other question has already been answered