I don't think F-100s ever carried anything on the centerline. Where would you put it, there just isn't room. The rear of the nose door ends at the front of the speed brake. The speed brake goes almost all the way to the main gear doors, and since the main gear doors are hinged at the centerline of the plane there just isn't room for a pylon. The gear doors and speed brake are colored black on this 3 view. It appears that the "special" weapons would have been carried on the inner wing pylons.