Digital BW, The Print

Hello,
  I am about to receive a set of EZ BW Neutral for my C84. The printer
now has the original Epson inks in it. 
   Obviously I take out the Epson carts and put in the MIS carts.
1. What is the best way to clean out the Epson inks (ie flush) after
putting in the MIS carts ? How many clean cycles ?
2. Can the old Epson inks be put back in at a later date if desired or
do you need new Epson carts (it is my wife's printer and I might get a
new C84 if I like the results)?

                     Stuart