Dear Mr. Kness,
Thank you for posting your request on History Hub!
U.S. Navy general courts-martial (GCM) records from 1951 to 1976 are in the custody of the National Archives at St. Louis, ATTN: RL-SL, P.O. Box 38757, St. Louis, MO 63138-1002. Please contact them for access to these records. Their email address is stl.archives@nara.gov. These records include Marine Corps GCMs as well.
We hope this information is helpful. Best of luck with your research!