Continuing research

Things I've successfully learned today:  40s car models, history of "first aid" as a thing that exists, how a man could end up separated from his family at the start of the WWII Japanese American internment.  I already knew that George Takei was awesome, but am reminded of it as I go through his autobiography. Clear, honest, unadorned descriptions of his time at Rohwer and Tule Lake, along with historical context and some serious blunt truth on the things you miss when you're four.

Things where I have failed at search: Can anyone recommend good resources on civil rights and interracial dynamics in late 40s Massachusetts?  I'm looking for fairly practical stuff: how much trouble will this character (who is African American) have getting into libraries, restaurants, or stores?  How segregated are most settings?  How much fuss are bystanders likely to make about an obviously interracial group wandering around?

Any insight into how people in the northeast would slot a Japanese American woman into those laws or cultural restrictions would also be awesome, but that may be something I'll need to try and infer from experiences in New Jersey.

The past is another country.  A country that is deeply fucked up.