I'll be marshaling again this year - give a wave on the 59th Street bridge. I'll probably have a blow-horn telling people there's free beer up ahead

We wait till the sweep trucks come and then book ahead. I do have to find the marshal line for the ferry this time - the extra 2 hour wait at the end was a bit sucky.
Ride back across the Verrazano: No way. There's a strict time limit on how long they close the bridge for, traffic is one way with no stopping (though a lot of people did but we were supposed to keep them moving - was actually a requirement from Homeland Security so if someone does tell you to keep moving they're not just busting your chops

). Best bet would be to peel off before the bridge or just tack on the extra 15 miles back
For first timers especially going up or going down the bridges and inclines - keep your eyes open! People slow down or just stop in the middle of crowds going up or wipe out at 25 mph going down - be vigilant to avoid a wipe out.