Undoubtedly '68 (or earlier) automatic, not a manual trans, not '69 and later due to the hose exit on the Therm AC valve. The cleaner would have appeared on 4 bbl SB applications up to and including 295 Hp L48 cars. L48 lid could have been chromed for the dress-up SS package, same lid.
1969 and later SB automatic cleaners like this have the hose bib turn to the passenger (left) side of the snorkel, not the drivers (right side) - heat stove on '68's is on the driver's side manifold, '69's are passenger. hose exits are designed to clip under the air cleaner base without passing under the snorkel.
Regards,
Steve