Here's Soc Sec Death Index Information for Cleophus. It might help to order a copy of his original application for an SSN #. He may have still been living with his parents and that would help pinpoint his father's location in order to identify him other "Ira Adair's" in the census. I mention that it MIGHT help.

Social Security Death Index
Name: Cleophus Adair
SSN: 564-36-3377
Born: 5 Jul 1931
Died: Aug 1970
State (Year) SSN issued: California (Before 1951 )

Here's what State of CA has on his death. If you order a death certificate it SHOULD have his father's place of birth on it and that will also help to pinpoint where to locate him (Ira) in the census indexes.

California Death Index, 1940-1997
Name: Adair, Cleophus V
Sex: MALE
Birth Date: 5 Jul 1931
Birthplace: Oklahoma
Death Date: 10 Aug 1970
Death Place: Los Angeles

Found this death listings on Ancestry:

Social Security Death Index
Name: Ira T. Adair
Birth: 8 Jul 1917
Death: 7 Jan 2006 - Grandview, Jackson, Missouri
Civil: Missouri

Here's another found on Ancestry:

Social Security Death Index
Name: Ira Adair
Birth: 8 Dec 1905
Death: Dec 1985 - Madera, Madera, California, USA
Civil: California
Other: Madera, Madera, California, USA

Here's the same person on the Millennium File from Ancestry:
Name: Ira Clarance Adair
Birth: 8 Dec 1905 - Cullman, Alabama, USA
Death: 13 Dec 1985

Hopefully, one of these two Ira's was the elder Cleophus' father.

Georgia Walker-Adams