Most likely one of the variations on the Ready to Ship label
IMHO these were attached to a bin, crate or pallet of identical pieces that were packaged at the sub contractor/supplier and one in the batch was labeled to indicate that the group was ready go and included number of units in the shipment, date, part number .....
For some items that were a hang tag (have seen those on later trunk hinges and many other parts over the year) were used instead but provided the same information
My best guess with the limited evidence