If I remember correctly
during the period of Oct '71 to Jan. '72 an order came down from the
Battalion level to paint all gun trucks black because the VC (NVA) had bounties out on certain trucks.  Some trucks apparently inflicted more damage than others and consequently some trucks had higher bounties.  The high command was not fond of their added popularity so their answer was to paint them all black so we wouldn't infuriate the enemy anymore then needed (imagine that).  I also remember it wasn't a very popular order because many of the gun truck crews had a lot of pride in their trucks and the job they were required to do.  They were thought of (and admired) as the hired guns of the transportation companies.

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