After posting my follow-up on Sunday, my uncle sent me some more details about the CCA calendars:

“Most of the calendars during the late sixties and early seventies were designed at the CCA Corporate Design Center, which was located in downtown Chicago. It was run by John Massey who was head of all CCA corporate design and promotional material. He had two brothers that worked for him. We referred to them the Kalfus brothers (not sure of the spelling). They did many of the calendars. John Massey used Helvetica type only on everything they designed. Bill Bonnell came later and may have designed some of the last calendars CCA did.”

Somebody ought to do a site about CCA’s design history. So many things like this are virtually non-existent on the web.