The pictures are so close, they are confusing. I see two air cleaners. One with the air shield and small notch on the pass side and another with no shield and the bigger notch on the dr side for the ac compressor. I’ve never seen one with the ac notch. It’s clear from the bottom picture that the bridges have been removed on the outboard carbs. I bet your right. They were modified for three Corvette carbs of three center Mopar carbs. I’ve used three center carbs at one time before. I did not modify an air cleaner though.