If I used real jacquard design software, like Arahweave or JacqCad, I'm sure there's an easy 1-button fix, but this wasn't really all that difficult once I wrapped my head around what needed to happen.
So I was able to finish the first abstract piece based on a painting by Connie Rose, and began another. Here's the original image, indexed to several values of 3 hues (see the color chip strip at the bottom of the image):
And the lower part of the woven image - I only got to pick #300 by quitting time. The blue isn't the same as Connie's - not as much green in it - but I think it'll work anyway. And it was the closest color in the stash.