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To get started with your research, we would recommend that you request his Official Military Personnel File (OMPF). In general, OMPFs for military personnel who were separated from the service between 1912 and 1999 are serviced by NARA's National Personnel Records Center (NPRC) in St. Louis. In many cases where personnel records were destroyed in the 1973 fire, proof of service can be provided from other records such as morning reports, payrolls, and military orders.
You'll want to complete a GSA Standard Form 180 and mail it to NARA's National Personnel Records Center, (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. If there is any information requested by the form that you do not know, you may omit it or provide estimates (such as for dates), but the more information you provide, the easier it will be to locate the correct file. For more information see Official Military Personnel Files (OMPF).
Veterans and next of kin of deceased veterans may use eVetRecs to request records. See eVetRecs Help for instructions. Please note that next of kin of a deceased veteran must provide proof of death of the veteran such as a copy of death certificate, letter from funeral home, or published obituary. For more information see Request Military Service Records.
If his record was destroyed in the fire, do you know his division and regiment? Many of them published histories after the war, and his exploits may be accounted in the history. Additionally, if you know the regiment and division, of worse came to worst, you could search the division's general orders for the orders awarding him the Silver Star. In World War II, valor awards always included a narrative of the action as part of the order.
And, of course, if you have his discharge paperwork, it may give the order number on it--which makes it even simpler
