To make a long story short, I managed to turn a 17 mile ride into a 26 mile ordeal with a wrong turn, a side trip, and forgetting something and having to go back. There's a full writeup in my blog.
I'm actually not that excited about this ride though, which is kind of strange. I really didn't want to do a new longest ride. I just wanted to do a challenging ride at 2:30, and then do it again at 7. It looks like that won't be happening though.