Any judge of a circuit court holding office on September 18, 1973 who is entitled to credit for prior service toward earning supernumerary status in a position other than as a circuit judge shall be entitled to have all such service credited toward retirement status under this article, provided he does so within three years from September 18, 1973, by notifying the Supreme Court in writing of the service for which he is at that time entitled to credit toward obtaining supernumerary status and for which he desires credit toward retirement under the Judicial Retirement Fund provided by this article. Upon receipt of such notice the Supreme Court shall make a judicial determination of the amount of such credit to which such judge is entitled and shall notify the board of control of the State Employees’ Retirement System of this determination, and such service shall be credited to such judge’s retirement benefits and shall be counted as time of service as a circuit judge under this article.