Well, Charlie, you've definitely piqued my literary interest, so I'm taking 25A. Those passages in Gatsby are some of my favorites. I'll have to reread it before taking the trip. Too bad I'll be doing it in Winter, without the surreal effect of the Summer heat described in the novel.
Also, thanks for the information that the Montauk ferry to Block Island is bicycles and pedestrians only. I finally checked out their website, and they're done for the season, anyway. The ferry from Orient Point seems to run year round.
I'm coming from South Brooklyn, so I'd probably just take local streets up to Williamsburg, Greenpoint, and Long Island City and find my way to Northern Blvd. I could take the BQE, which I ride down to the Belt Parkway to go to Floyd Bennett Field, but it's a little harsh on the tailbone.
Anyway, I'll report back once I've made the trip.
Jeff