OPINION — AG — QUESTION: "IS AN ELECTED COUNTY OFFICIAL AGE 59 OR OVER ELIGIBLE TO BECOMES A MEMBER OF THE OKLAHOMA PUBLIC EMPLOYEES RETIREMENT SYSTEM IF HIS COUNTY BECOMES A PARTICIPATING EMPLOYER ON JANUARY 1, 1965?" — NEGATIVE CITE: 74 O.S. 1963 Supp., 911 [74-911](1), OPINION NO. 63-413 (BURCK BAILEY)