The U.S. Army, on the strength of two technical falls and a shutout, edged the U.S. Marines, 13-12, in the deciding dual meet at the Armed Forces Greco-Roman Championships held at the U.S. Marine Corps base in Quantico, Va., March 30.    The Army won just three of the seven matches. However, technical fall wins by Glenn Nieradka (60 kg/132 lbs.) and Dremiel Byers (120 kg/264.5 lbs.) and a 7-0 shutout win by Keith Sieracki (74 kg/163 lbs.) gave the Army the one-point win.     Scoring wins for the Marines in the dual meet were Duaine Martin( 55 kg/121 lbs.), James Shillow (66 kg/145.5 lbs.), Kenny Owens (84 kg/185 lbs.) and Dan Hicks (96 kg/211.5 lbs.)    The Army finished with a 3-0 dual meet record, followed by the Marines with a 2-1 record. The U.S. Air Force was third with a 1-2 record and the U.S. Navy was fourth with a 0-3 record.    Both the Army and Marines won three individual gold medals each. Army individual champions were Nieradka (60 kg/132 lbs.), Keith Sieracki (74 kg/163 lbs.)and Byers (120 kg/264.5 lbs.). Marine Corps individual champions Martin( 55 kg/121 lbs.), Shillow (66 kg/145.5 lbs.), and Hicks (96 kg/211.5 lbs.).    Claiming the other individual title was Aaron Sieracki of the U.S. Air Force at 84 kg/185 lbs. All seven individual champions had perfect 3-0 records in the tournament.    The Armed Forces Freestyle Championships are scheduled for Sunday, March 31 at Quantico, Va.