eddie,
The early V marked tools like wrenches, sockets, extensions, handles, and ratchets did not have part numbers on them until about 1975 (Easco era).
Some other tools, like WF (Western Forge) marked screwdrivers had part numbers on them from as early as 1964/1965 when they started producing the Crafty screwdrivers and certain other tools like punches, chisels, pliers, and adjustable wrenches.