Section 3. If the arbitration agreement provides a method for the appointment of arbitrators, such method shall be followed. In the absence thereof, or if the agreed method fails or for any reason cannot be followed, or if an arbitrator appointed fails or is unable to act and his successor has not been duly appointed, the superior court on application of a party shall appoint the arbitrator. The court shall submit to the parties a list of five persons experienced in labor arbitration from which each party may delete two names and the appointment shall be made from the name or names remaining. An arbitrator so appointed shall have all the powers of an arbitrator specifically named in the agreement.