John, the 68-69 Corvette judging manual states that the bypass hose for the 427 used a Wittek number 10, single screw clamp, type D (see drawing below). Comparing the two pictures to the drawing, I would say the top picture is right, but that screw sure looks awful long!
Of course, there was probably an overlap period in early 1968 when either could have been used.
Ed