Thanks for the compliments.
I dug through the DMV code and online and couldn’t find any clear evidence it was illegal in this application of the blue marker lights. I always thought if I got pulled over and informed I was incorrect, I’d swap them out.
That tail lamp channel piece was actually part of the frame extension for the camper that I cut off and repurposed.
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I live in California, but identify as a Texan 
"If a job's worth doing, it's worth doing well"
Survivor "
Lil’ Mint" (67 c10 40k mile light green original paint)
Project "
C10 Fever" (68 factory black 396 swb)
Project "
Little Sister" (70 c10 blue original paint refresh)
Project "
Blue Bomb" (70 c30 blue original paint refresh)
SOLD
Project "
Vitamin C" (71 c10 orange original paint refresh)
SOLD