Thanks everyone! The one street that wasn't in a list of current streets was Asylum Street. I am pretty sure this is now Franklin. I was able to find every other street I was looking for, and of all the addresses on Main, only 3 were no longer there... 244, 246 and 248.. now a kind of triangle with flower boxes at the corner of Franklin. Not surprising that these buildings are no longer there, as these addresses were from the city directories in the 1860s. It was fun looking for all the places, though!