The records for either Ellis Island or the other ports in US were written up at the port of departure being Bremen, Hamburg,or Fiume and no name change came about until our ancestors were in the "new land" and either willingly or unknowingly their surname got "americanized".
KRATZ spelling does seem German.
You did not answer any of the questions I posted.Were your ancestors naturalized citizen or had social security numbers?http://ssdi.rootsweb.comhttp://ssdi.rootsweb.comYou need to establish a place of birth in the "old country" in order to proceed with the research.
What language did your ancestor speak?Have you found the family in a 1930 census?
Scratch could have been SKRACZ. Did you try to find your ancestor coming thru EI with One Step/Gray form?www.stevemorse.org http://maxpages.com/polandhttp://maxpages.com/poland