There is no early and late HZ decal...... There is only HX Sandman decals and HZ Sandman decals. I have checked the individual decal part numbers rather than the decal set part numbers.... the sets seem to have the typo's in the parts books but the individual decals have all the correct part numbers.

Below are the tailgate decal part numbers......

HX tailgate decals




HZ tailgate decals


Note as Jason has said the DY3 part number has been superceded in HZ due to the colour change of the red.
Part numbers tell the story.