Digital BW, The Print

>
>    If there is a very large volume to purge then I could just do a 
> power
>  clean cycle, but that will waste a lot of the color inks as well.
>

Don't know about the compatibility of the two inksets mentioned, but 
with any other two inksets the standard advice is to install flush 
carts (you can make them yourself with distilled water), and flush 
until the lines are absolutely clear, preferably including a couple of 
days in there where the printer is just sitting with the flush in the 
lines.  The ink wasted is a lot cheaper than replacing a head 
hopelessly clogged with incompatible inks.

James