Assuming the bearing surfaces are the same angles between English and Italian (no reason they wouldn't be), a 1mm spacer under your fixed cup should suffice. The lockring on the NDS can just screw in a little more, if necessary. They are only 1mm or so different in length, and that length is added between the 'cones' of the spindle.

Or it might be fine with no spacers at all. 1mm of variation in chainline is not important, and the NDS cup is threaded its entire width.