I watched a documentary on the tragic night and I recall an interview with the US Coast Guard captain who went out with the Anderson in the search and rescue effort and he said those were the worst seas he had been on and that included about 25 years service on the Gulf of Mexico and elsewhere like that.
It’s been a few years since I was there - but there’s a museum right by the Duluth ship canal where the ore and grain boats go in and out.
The museum is a couple of stories taller than the canal. back on November 10 1975, someone took pictures of the canal during the storm. I do recall that the pictures made Lake Superior look like a storm out on the ocean.