Andy,
Yes, I use the marine standard for wire colors. Blue for lighting, brown for pumps, gray for nav lgts, pink for fuel sender, and have been using yellow for grounds for several years now. Yellow actually stems from a CE requirement that came out a few years ago wherein any boat that had 120VAC on board, the 12VDC grounds have to be yellow to differentiate between 12VDC negative and 120/240VAC hot (both being black). I was an engineer at Proline then, and we determined that rather than stock different harnesses for US boats and for European boats, we would simply have ALL of our harnesses changed to yellow grounds, regardless of whether the boat got 120VAC or not. Saves inventory costs. Now, per ABYC E-11, yellow is an acceptable color for 12VDC ground, regardless of the boat's destination.
I would like to use the various stripes (brown w/white, brown w/blue, etc.) to further differentiate functions and to assist in trouble shooting, but the cost of a re-wire would grow substantially. The sources I use (Greg's Marine wire and genuinedealz) have both told me they could stock the striped wire, but the cost would be WAY more than the solid colors...
BTW, Dave's Scarab is back at the house for more work. Going to add a second C80 display and completely re-do that electronics flat, as well as install a Flo-Scan...