So, SSH, What is the largest carb that will fit under the 273's air cleaner?

How difficult is it to find a "real" 273 carb?

How much would it cost the OP to have you do such a carb?
Or the largest carb mentioned above?

I am assuming the OP wants it to "look" original, but I don't believe he's talking about looking original to a concours judge. So what's the best way to go to feed that 360 and still keep it looking like a 273 to the casual bystander?

Would it be possible to modify the stock air cleaner base to work with the later larger OD airhorns?

R.