I don't think the manual choke or air cleaner attachment have much do to with the issue here. It's the bottom/manifold interface we are talking about. Now that I posted a picture and you know the "bites" are normal and it physically fits, What is keeping you from using this carb/moving forward? Your air cleaner won't mount?

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn