Procedural Stitches (?)

Hello!
I'm wondering how I cam make my stitches procedural? I can use fill layers and masks to make everything else I do procedural but I'm constantly re-drawing my stitches. I have the same sweater model that I re-render again and again with new designs and it would go INFINITLY faster if I could only procedually change the colour of my stitches.
Is there a work around for this? Or am I ignorant to a current method? 
Please help!

Thanks, 

-Brendan