I know I'm in Australia, but... I have a EA81 manifold with the same bolt pattern as the EA82 carbs. I am pretty sure my dual carb manifold has the bigger bolt pattern too. I also have a manifold and carb off an 83 and it has the smaller size. I was thinking maybe it was a after 84 thing. Like after 84 they went to simiular carbs as the EA82s?