Does your father remember filing a copy of his DD214 from the Navy with the county VA office where he returned to live. Did he claim any GII. Bill Benefits or state benefits for continueing education or housing loans? Merchant Marine service was granted WWII Veteran status till later. Here is another link to look at: www.vba.va.gov/bln/21/Milsvc/Docs/MerMar.doc

I found a David A. Natvig age 21 was a crew member of the S.S. Marne when it arrived in the port of NY Sept 17th 1946, left Taranto, Italy Sept 4th 1946. Ship continued on to Port Arthur, Texas where he was to be discharged. Previous time at sea 18 months. Shipping agent was American Trading and Production Corp. Owner was WSA,USA

There are two pages I can try to email to you directly but if it doesn't work I can print them out and mail them to you. My email is ancestryseeker at gmail dot com. Send me an email first and make sure your spam filter will accept my email back with attachments.