US Census 1920 San Francisco:

Woods, William, Head, 47, Arrived 1906, IOM, IOM, IOM, House painter
Margaret, Wife, 46, Arrived 1906, IOM, IOM, IOM
William, Son, 23, Arrived 1906, IOM, IOM, IOM, ?? At Sea, Pacific St Ship Co.
Anna, Dau, 16, Arrived 1906, IOM, IOM, IOM

The Margaret is most likely Margaret Jane Quilliam who married William Wood 25 May 1895 St George Douglas.

Actually, I'm collecting a list of Manx-born in the 1920 Census and will post when finished...

Kind Regards,
BB