Digital BW, The Print

Hi all !

I'd like to order this new inkset for my 7500, but Paul's instructions
seem obscure to me on one point : the LC position composition.
This ink must be hand-mixed until available pre-mixed from MIS, but I
just can't understand what Paul explained... Here's the snippet :

"Light Cyan position = This is a new medium-density gray ink.
It has a density half way between the C and Y position inks, which
makes it darker than the old standard FS-M-position inks. 
MIS may have this available in early 2005. 
In the meantime, this is the formula,which is based on
readily-available MIS inks and easy to mix:
60% FSN-M,
33% EZ-N,
7% EZ-W."

The question is : which ink position should I order for EZ-N and EZ-W
? These look like inksets names, not an inkset/ink position reference,
as far as I can tell..

Thanks for any help.

Christophe