Cartographer?
Some sort of drafting? Maybe shipbuilding or something? Back in the 1970s in CA, I imagine it could be something related to the defense industry.
I read through the script. She is a drafter for Motel 6, believe it or not. Odd writing.
"First woman to work in the Continental Can Company drafting room," says the movie voiceover. She was a drafter, which my mother was also.