Even in the 50s and 60s it was not a good idea to fool around with the Canadian-US border nor border agents. Especially if you were not a citizen of either country.
Funny, I remember family crossings at Niagara Falls and North Idaho in them 50s and 60s that were very casual, low key and all you needed was a driver license for ID. I arrived in Montreal on a business trip in the early 90s expecting the same DL ID to suffice. I nearly got sent back home at the airport for arriving without a passport. They let me in with a stern reprimand.