There are several WW2 War Diaries in the National Archives, Kew, covering RE units with 74 Coy title, but none have been digitised so will require a trip to Kew, using a private researcher or getting the NA staff to copy the document.
To see what is available at
http://discovery.nationalarchives.gov.uk/advanced-search enter 74 Coy Royal Engineers, reference WO, dates 1939 1945