Judgments of special and summary courts-martial shall be subject to review by the Adjutant General only, except that sentences of Bad Conduct discharge shall also be subject to review by the Governor; and such judgments may be affirmed, set aside or modified; provided, however, no higher or greater sentence, punishment, penalty, fine or forfeiture than that imposed by the court-martial shall be approved; otherwise trials and proceedings, including nonjudicial punishment, pretrial proceedings, post-trial proceedings, search and seizure proceedings and proceedings by all courts and boards, including review proceedings, shall be in accordance with the Manual for Courts-Martial United States, as now existing or subsequently amended, procedure for courts of inquiry, and retiring boards, and other procedures under military law, as may from time to time be prescribed by the appropriate secretary of the respective services.