I believe the sill mouldings being referred to in the sport package are actually the lower body side mouldings below the doors and black paint below those mouldings as on the formula S package. If on the dash, it would have been referred to as a black "applique" on the instrument panel.
I am still curious about the black on the dash, as i have never seen that before on a 67-69 barracuda, standard or formula S