Hi Peter. Where in the US did your grandfather live? When was he born, roughly?

Personally, I never start by searching for a passenger list. Especially with a name as ripe for transcription errors as "Boezowicz." I start by looking for a naturalization. Because if one exists, you'll learn exactly when and where the person arrived, and, for later arrivals, under what name.

If he never naturalized, use the census as a guide to narrow down a smaller time frame for arrival. You want as many limiting factors in your search as possible. Also keep open the possibility that he may have come through another port, even if he lived in NY.
Hope that helps.