Napatree, you should be fine but you might not want to go at dead low. My alarm has been going off at 6 ft at dead low, but, I'm not sure how accurate that is as I only draw 5 ft.
Block on the 4th, eek. Not a chance for a mooring IMHO. Most people come days before to grab a spot. The place is a zoo anyway.
Fisher's Island, West harbor is the best anchorage I think. Noank has a decent anchorage just across the sound.