Hip vernier? Which opening are you talking about, the circle-bar?
Just to clarify, are you talking about the hip armour, which covers the engine intake, or the wing root armor, that covers the VF-25's 25mm wing root gun?
On what I call the wing root armor, there are three openings, the front, which is thought to be the opening for the VF-25's 25mm gun, although I'm begining to wonder if the opening actually lines up with the 25mm gun or not. Then there are the two ovals behind it, which based on the line art published in the August HJ and the new Frontier Archieves books, show cylinders on the rear of the armor (behind the ovals), which to me don't look big enough to be guns, but who knows?
Graham