Chevrolet pin - "SELL PRICKLY FUZZIES"

[Mr70]

Look at the dates shown on that,(July 13 to Oct. 5th),that should be your first clue.It's referring to selling the cars and trucks that have been on the lot too long,(both new & used),as they wanted to get rid of the old to make room for the new that were,as they say,growing whiskers or beards.
That was an old expression among dealers and salesmen.And by those campaign dates,it looks like this is Zone or Region specific,meaning I don't think this is a Central Office button,and naturally the Zone & Regions wanted those over-age cars and trucks sold in time before for the new model year introduction period.