The raid was planned in a Daly City apartment. Preparations began in early 1977, when Joe Boys members began acquiring the weapons that would be used in the massacre; during the summer of 1977, Tom Yu, a leader of the Joe Boys, convinced a longtime friend who owned a home in Pacifica to store the weapons, wrapped in cloth, in the front closet of that home. On August 29, 1977, Yu met with Carlos Jon, a member of another gang; Yu asked Jon to keep track of Wah Ching and allied Hop Sing Tong gang members over the upcoming Labor Day weekend, showing special interest in where they gathered late at night. The conspirators decided to target the Golden Dragon because it was a favorite hangout of both the Wah Ching and Hop Sing Tong. The planned raid would also financially damage Jack Lee, a Hop Sing elder who co-owned the restaurant.