WWI Draft Registration, 5 Jun 1917, Idria, San Benito, CA, Clifford was single, states birthdate as 2 Sep 1890, Keokuk, IA; he was tall and stout, had blue eyes and red hair. ‏(Birth date author has is 28 Sep 1890. Place of birth, Keokuk, IA, may be incorrect; most likely he was born at the home of his paternal grandparents, Cedar Twp., Van Buren County, IA.)‏
WWII Draft Registration, 27 Apr 1942, Centralia, Lewis, WA, Clifford stated his birthdate as 28 Sep 1893.

Clifford owned a hardware store, "Loofbourrow Hardware & Plumbing", in Centralia, WA. He died at home, Centralia, WA, 8 Dec 1943 at age 50.
Source: Newspaper clippings regarding Clifford's death were sent to me in a letter from James W. Loofbourrow, Oklahoma City, OK, 18 Jan 1994; Centralia Chronicle ‏(undated)‏ and The Tacoma Times, Saturday, 11 Dec 1943.