Za698. WWII SW Bataan Hand drawn map from Philippine Veterans Affairs Office (PVAO).
This confirmed that the location “Signal or Signal Hill” existed. Look close and you can see that Trail #7 starts there!
The Philippine Veterans Affairs Office (PVAO) has a Philippine Archives Collection
The Philippine Archives Collection is a group of records at the US National Archives that constitutes an invaluable source of information on the Pacific war, particularly concerning the treatment of prisoners of war (POWs); military operations in the Philippines, 1941-1942; guerrilla warfare in the Philippines; and conditions in the Philippines under Japanese occupation.
This is the URL:
http://collections.pvao.mil.ph/