Digital BW, The Print

Just ordered a set of 3mk inks for my R1800 and realised after I put 
the order in that I only ordered 2 of the 3 cleaning carts, I'll be 
missing the MK cleaning cart.  Will it cause problems if I just flush 
the PK and Glop positions and use the eboni in the MK position without 
flushing that position first?  I figure out of all three, the MK is the 
best one to be missing since it will be an MK ink replacing another 
MK.  As far as how the cleaning carts actually work; do you just put 
the cart in, run a head cleaning, remove the cleaning cart and replace 
it with the eboni cart?  I've worked with another bw inkset in this 
printer before (NK7), but there was no use of cleaning carts or 
flushing so I'm new to this part of the workflow.  Thanks for any help.