Series is whole-numbered in the issue code number (found in a bottom panel of the first main story) throughout the run.
Whole-numbering is on the cover of #264-270, but not in the indicia.
Whole-numbering is added to the volume-numbering in the indicia of #449-510.
Whole-numbering is also on the covers of the Gold Key editions of #462-473 and the Whitman editions of #474-510.