Nice Hornet with Clifford Head

What do those air cleaners with the long necks come off of? I've got like a 1 3/8" stack of gaskets/insulators under the carbs to level my short neck air cleaners with the taller Clifford head.

Those are Jet air cleaners. Same as the big cars, just a longer throat. I actually use one on my big six Twin H. I had a pair of Jet air cleaners, and rather than cutting them both down to Hornet size, I just did that to the front one. That way the tops of the air cleaners are 'even' with each other.