They have talked of a "Governing Body" BEFORE 1971 for decades.
*** w71 12/15 p. 757 A Governing Body as Different from a Legal Corporation ***
According to the apostolic example of the first century C.E., these dedicated, baptized Christians known today as Jehovah’s witnesses have a governing body, as specifically noted from the year 1944 onward. This governing body has through the years been associated with the publishers of the Watch Tower magazine and the Board of Directors of the legal religious corporation now known as Watch Tower Bible and Tract Society of Pennsylvania
*** w90 3/15 p. 17 par. 9 Cooperating With the Governing Body Today ***
For years, the visible Governing Body came to be identified with the seven-member board of directors of this corporation established to publish the Bible study aids needed and used by the Lord’s people earth wide.
*** w90 3/15 p. 18 par. 13 Cooperating With the Governing Body Today ***
Until 1971 those of the Governing Body were still identified with the seven members of the board of directors of the Watch Tower Bible and Tract Society of Pennsylvania. The Society’s president carried the main load of responsibility for making decisions affecting the operation of the Society’s branches throughout the world.
*** je p. 26 Shepherding God’s Flock in Unity ***
In 1909 they moved their headquarters to Brooklyn, New York. Through the years the directors of the Watch Tower Society and other closely associated, spiritually qualified, anointed men have been serving as a governing body for Jehovah’s Witnesses.
The Governing Body consists of a group of anointed Christian men (13 in 1986), including 7 serving on the board of directors of the Watch Tower Society.