Dryden, I meant to note 8dn as a clue without a misprint, not 9dn, which indeed has a misprint, though a rather obscure one, I thought. As the answers to these two clues have already been revealed, I don't think it's necessary to discuss them further.
I agree that this was a bit of a slog, with the fact that only 35 of the 49 clues contained a misprint adding an extra complication even after I'd identified the quotation (fortunately, I'd solved a lot of the early across clues fairly quickly so I did a Google search for what I guessed to be the first four words). The puzzle was certainly very clever technically, but I didn't get the "wow" sense on finishing it that a really good puzzle provides.