I don’t think Gordon Lightfoot was trying to rhyme “go” and “most”; “As the big freighters go, it was bigger than most” was one line in the second verse. Some lines of The Wreck of the Edmund Fitzgerald did have internal rhyme: “The ship was the pride of the American side”, “Old Michigan steams, like a young man’s dreams”. But not all of them.
Anyway, I’m willing to give Gordon some slack, for the sake of the beautiful rhyme in the fifth verse, that punches home the tragedy:
“They might have split up, or they might have capsized
They may have drove deep and took water.
And all that remains, are the faces and the names
Of the wives, and the sons, and the daughters.”