Kevin Mac Donnell (whom we'll hereafter refer to as "The Kevin") gives a
mountain of evidence for "Adventures of Huckleberry Finn" as the title
for Twain's novel, but he doesn't mention the first British edition,
which actually preceded the first American edition.  It was in fact,
published in 1884, and the American edition didn't appear until 1885.
Wasn't that British edition titled "The Adventures of Huckleberry Finn"?
That seems to me to give it legitimacy as an alternative title.  -Jim L.