Notwithstanding the provisions of Kan. Stat. Ann. § 76-3a15 (repealed L. 1970, ch. 371, sec. 19) to the contrary, all officers, employees, faculty and other persons in the employ of the university of Wichita who became members of the Kansas public employees retirement system on July 1, 1964, who are retired on the effective date of this act, shall be granted prior service credit for service with the university of Wichita prior to its acquisition by the state of Kansas if such officer, employee, faculty or other person was not eligible for or did not come under the retirement programs through insurance companies which were available to officers, employees, faculty and other persons in the employ of the university of Wichita prior to its acquisition by the state. Except that no more than three (3) years credit shall be granted to any member and for the purposes of computing the prior service benefit, a prior service annual salary in the amount of compensation paid to such member during the last (12) months next preceding July 1, 1964.