Rear Valance 67-69 Barracuda Dual Exhaust Cut Outs

Did the rectangular dual exhaust cut outs only come on Formula S Cuda's ? if yes, then all other factory dual exhaust Cuda's would have come with the circular cut outs?
If possible, can someone please provide a clear large close up pic of the factory rectangular cut out on the rear valance, that would be very much appreciated, thank you.