According to this, there's no smog INSPECTION requirement for 1975 and older model year gasoline powered vehicles.
https://www.dmv.ca.gov/portal/dmv/de...smogfaq#BM2535
I lived in CA for over 30 years and never heard of anybody getting smog checks on 1950's vehicles. Cars in the 1950's weren't designed to pass smog.
I've never heard of 5-year smog check intervals either. Smog checks are biennial. Can you please provide a link which corroborates your claims?
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