Wrong. At first glance there is visible differences. The venturies are smaller, and the idle mixture metering is different. I haven't checked the rods and jets for sizes. I am willing to bet they aren't as rich as the 318's.
Edit:the first thing you will see is comparing the flat part of the air horn. The super six is thicker. The PCV tube is straight on the V-8's.
I am trying to remember if the 318 carbs have holes in the butterflies.
The idle screws are probably different on the S6's. I haven't been into one in years.