I know there is an expert that will tell me the proper thing to enter for the death location. My grandfather's nephew was killed in WWII,
May 20, 1944, USS LST-174, West Italian Coast operations, KLOFTA, Melvin, SEA2, 7232028, (CasCode6421), dd May 20, 1944 (bp/1)
What should I enter for his death location?
Probably Anzio. https://en.wikipedia.org/wiki/Battle_of_Anzio