Sephardic Jews in late 18th-century Boston?

Question

I have recently encountered circumstantial evidence that some of my 18th-century Boston ancestors with unusually sparse documentation may have been Sephardim.  One individual has the very unusual surname Cloues.  The more common surname Lewis may have been adopted by the son of a Caribbean sugar plantation owner engaged in the triangle trade.  Can anyone identify Sephardic profiles from Boston in the era of the American Revolution or suggest Sephardim data sources for this time and place?

Answer 1

https://en.wikipedia.org/wiki/History_of_the_Jews_in_the_United_States

http://nationalhumanitiescenter.org/tserve/nineteen/nkeyinfo/judaism.htm