If you go to Quinpool Tailor on Oxford St in Halifax, they have some photos (or used to anyway) of the prototype square rig for MS and Below. I know it's not a pre-1968 photo because it's a sailor in square rig with a modern (MS) rank badge. Unfortunately, this idea was short-lived because the CDS of the day (who was against the DEU project to start with) put his foot down and refused to allow different uniforms based on rank. He also forbade sweaters as "too British." We didn't get sweaters again (we had them in green) until he retired. Everybody, except the Navy was issued a winter-weight and a summer-weight uniform. This was because some idiot decided we need two blue (winter-weight) jackets more than we needed a white tunic. The Army, by and large, hated their tan uniform and no one in the Air Force ever wore the winter-weight version because it was the same colour as the other one anyway.