Notwithstanding the provisions of Kan. Stat. Ann. §§ 74-4913 to the contrary, any employee of a participating employer who first became a member of the Kansas public employees retirement system on January 1, 1969, who was first employed by said participating employer on January 13, 1947, until January 12, 1959, and was reemployed by said participating employer on January 9, 1967, shall be granted prior service credit upon retirement for said service prior to January 1, 1962. The prior service benefit shall be computed by using a prior service annual salary of one thousand eight hundred ninety-nine dollars ($1,899).