DJ,
I have completed an initial survey of my reference material, and can only give a partial report at this time
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The yellow strip appears to be a long distance recognition symbol - "I'm US - don't shoot" I have photos of other 1st Armored Division tanks in Ireland, befoe shipping to North Africa with teh same turret strip, but in white. Both the 1st AD Stuarts and Lees carries this strip in yellow. It was changed to yellow as white was too visible to German gunners. It appears to be a pretty common ID symbol, as I also have photos of 5th AD tanks with a white horizontal turret strip.
I do have another reference that breaks out the unit markings, the yellow rectangle and circles, and the little colored lines on teh turret stars. I will get back to you.
Jeff