Cruce Family Genealogy Forum
While browsing through the Texas on-line archives for the surname "Cruce" I ran across what appears to be your William Preston Cruce born 12 January 1872 born Armstrong County, TX. He was listed in the 1917-18 ranks of males living in Texas. I'm not sure if the database is for those who are subject to the draft or who have already served in the military. A note says "Wife lives at Pitola, Texas."
Maybe this will give you a clue where to look. Good luck.