My memory is fading but not long ago some posted a video, or maybe I seen it somewhere else, that actually show a line worker putting a mark on the inner fender. Basically signifying that it was ready for the next process, or maybe it was a dept. identifying number/letter. If I can find it I'll come back and post it.
I'd had also "heard/read" that some of the marks indicated to the next operation a specific part, or option?
Didn't answer your question but I at least muddled the water some more!
