1970 Z/28 Air Cleaner - Help ID

[dvss1]

I really cant make out what the green numbers are. Usually from the ones I have seen, its a date. The base is defiantly real especially with 90 degree vent tube comming out of the bottom however I have never seen any factory or srevice replacement with that big of gap in the center of the snorkels where they attach to the base. Dr. 409 was making snorkels for the 409 air cleaner which were similar to the z28 or z16 air cleaners. Also the hems on yours dont look straight or parallel to the snorkel. Maybe its just the pics.