Whenever a vacancy occurs in any position in the service of the Municipality which is not exempted under the provisions of § 10.02 of this Charter it shall be filled in the manner provided in the personnel ordinance. Promotional examinations may be restricted to present employees, or if recommended by the City Manager, they may be opened to qualified candidates from outside the Municipal service, by resolution of the Council. The names of the three (3) eligibles standing highest on the promotional eligible list shall be certified to the appointing authority and he shall appoint one (1) of the three (3) so certified, as may be provided by ordinance.