... There are inks (black) dedicated to making film positives. One such brand is "Black Max".
That's an interesting specialty. Google just got me to http://www.silkscreeningsupplies.com/product/RipComboBLK1430
It looks like it is dye ink. I've been using Noritsu dyes bought in bulk. See, for example, http://www.paulroark.com/BW-Info/1400-Claria-Noritsu-2K2LK.pdf
They are supposed to be very fast drying. My idea is to centrifuge the original ink out of the cartridges
I do have a centrifuge, but I've never tried that method. I just pull the ink out of cartridges with syringes and bottom fill adapters. I also use these to pull the air out of the outlet after filling.
MIS Associates aka www.inksupply.com makes lots of accessories that might be useful to you.
See, for example, http://www.inksupply.com/accessory.cfm?action=find&the_cat=1
If you just use the one K position, you can fill the others with the generic base I use. See http://www.paulroark.com/BW-Info/Ink-Mixing.pdf . You don't want the other positions to be dry -- bad for the head.
Good luck with the project.
Paul