Digital BW, The Print

Just wanted to confirm that the CMY cartridges all do use the exact 
same ink. I'm about to buy some bulk ink, and noticed that MIS has 
separate bulk inks for the C, Y, and M positions.  I'm guessing I can 
just buy one of those, and put it in each of my three separate 
refillable cartridges.

Also, if Paul reads this, could you provide a bit more info on how 
you "prime" the cartidge.  Am I to understand that you actually pull 
the "gasket" out near the print head.  (My problem is that I can't 
picture how the cartridge works, even with the photos I've seen.)

My first runs with the throw-away cartridges were stunning.  With how 
fast this printer drinks the black ink, and how much I'm printing, 
refillables are the only way to go.

Thanks.