Joe,

Subtle differences in leading edge or trailing edge sanding or even placement and angle of your meter relative to the fuse centerline can lead to different readings. Since the E-Motion has front and rear carbon fiber tubes, any side being low will cause the opposite side to be a little high which will show up as the stab out of square to the fin. The stab halves are not adjustable so whatever happens to one side would affect the other side. Since the fin and stab are square, I would look to a tool or possibly placement induced cause.