I believe that for the 68 barracuda there is one screw in each of the headlight trim pieces and the 67 has none. I also believe the corresponding trim around the grill area has one screw in each piece for both the 68 and 67.
If the kit you are talking about has two beveled screws for the headlight trim then are the screws for the grill trim different (not beveled?) - that seems odd since they are visible together and fall within the same visual line that continues as a black recessed stripe.