This is the first page of a Willie Cockrofts service record, unfortunately not your Willie Cockroft I dont think . Enlisted in the army at the outbreak of the war, but only served until 1915, and restricted to "Home" duties for some reason. I can only think it was because he was an insurance salesman, so that made him a bit more educated, therefore not as disposable as the general rabble.
http://i117.photobucket.com/albums/o72/rik242_2006/clive.jpg[/img]
Unfortunately I cant find a match given the info, nor can I for my surviving relatives. I think you have to be fairly lucky as only about 40% of the records remain.