Finally found him in the 1920 census. He was still an alien...you might be right..he may never have become a citizen.
In the 1920 census he is listed a Michale Sanfillipps in the index. The ED is 181 in Brooklyn, Kings Co., NY, page 8a. In this census it states he arrived in 1888. Something to check out. Cannot find him in 1930 so far.
Just found a listing for Michele Sanfilippo in Brooklyn in 1921. This is his listing for the Declaration of Intent. These are first papers filled out in the application for naturalizaiton. The volume number is #247 and the page is 60. If you live in NY you can probably access this at the public library or at the Family History Library near your home.
This should list ship of travel, date of arrival, and maybe his home town.
Tried the given website...but couldn't get it to load...said something about a time out connection error....do you have a current address on that site? would really like to find out information on the immigration before Ellis Island...I need 1874 and 1880. Do you have any suggestions?