The website "Spy Culture" has the story.
"Executive Action is perhaps the most famous conspiracy thriller about the John Kennedy assassination, with the exception of Oliver Stone's JFK. Recently released CIA records in the CREST database show that they were keeping an eye [ on ] the production and how it was being received. The articles even detail how the CIA may have threatened or tried to stop production of the film.
If you do not know what the CIA's CREST database is, well, shame on you.
Okay, these documents are not in the JFK Records Collection, so they do not have RIF numbers. They are in the CREST database.