Actually, US Army figures are fine for LTV crews in the Pacific Theater. The Army had a number of Amphibious tank battalions that crewed LTVs in most of the major operations in the Pacific. One unit in particular comes to mind, the Army 708th Amphibious Tank Battalion. They were formed in September 1943 from the 3rd Battalion of the 69th Armored Regiment, 6th Armored Division. The 6th Armored Division would remain the parent organization for the remainder of the war, but while the 6th Armored fought in Europe, the detached and redesignated 708th Amphibious Tank Battalion served at Kwajelein Atoll, Enowtek, Saipan, Tinian, Okinawa, and the Philippines. The Army 708th Amphibious Tank Battalion served both the Marines and Army, carrying elements of the 4th Marine Division ashore at Saipan and at Okinawa. In fact the 708th suffered more casualties than any other amphibious tractor/LTV unit at Saipan, including Marine Corps tractor units. The Army's 708th Amphib Tank Battalion ultimately was awarded TWO Navy Presidential Unit Commendations for its actions at both Saipan and Okinawa in support of the Marines.
There were a number of other Army amphibious tank units that also served with distinction in the Pacific, so don't be shy about using Army figures to crew your Pacific Theater LTVs. The Army was there, even taking the Marines ashore!