And, while I think most would agree that it is a critical argument rather
than a hack copycat attempt... *The True Adventures of Huckleberry Finn* by
John Seelye would be a good book to add to your list.  There are also a
number of shorter works, also critical, that use the voice of Huck, Tom,
Jim, and Jim's son... if I remember right.  The titles/authors aren't coming
to mind immediately though.

Michael