here's my thought is there a way using the Crown Heights riots as a POD could you make Jews or African-Americans (at lest northern inner-city ones) a Republican voting block
No, because it boils down to a fundamental ideological divide that will not be overcome. If the GOP was the 1960s party of Nelson Rockefeller and not the 1990s party of Newt Gingrich, maybe. Since that is not the case and is impossible with a 1991 POD, not happening.