[David O McKay Diary]
This morning at 8 o'clock, met with the Temple Committee, consisting of the Presidency, President Joseph Fielding Smith, Elders Harold B. Lee, and Spencer W. Kimball. I asked Howard McKean to present the proposed plan of preparing the present Temple rooms in the Salt Lake Temple to experiment upon the new plan of presenting the ordinances by use of screen and visual aids. It was decided that we can use the Assembly Room in the Temple to set up a stage to make the experiment without making important changes in the present rooms.
[Anderson, Devery; The Development of LDS Temple Worship, 1846-2000: A Documentary History, http://amzn.to/TempleWorship]