[160B]

Based on page 7-2 of the Restoration Guidelines and Judging Standards the pedal on the left is "Typical pedal with lubricator fitting used from May 1930 to end of production" and it looks like the one on the right is "Typical pedal used from Nov 1928 through May 1930 without lubricator fitting" The size and location of the hole indicates it was an owner modification to add a lubricating point.