LaMar S. Williams is instructed by President David O. McKay and his counselors that those living in polygamy could be baptized but "were not to engage further into this practice."
LaMar S. Williams, Journal, 1960 December-1965 November, December 19, MS 82, Church History Library
On November 21, 1962, I was set apart as the first missionary to the colored people in Nigeria to assist Apostle N. Eldon Tanner prparatory to the establishment of the Nigerian Mission by President David O. McKay ^(mouth), President Henry D. Moyle, and President Hugh B. Brown. I was asked previously by President McKay to prepare to go for a period of not less than six months to baptize the worthy individuals into the Church and to organize them into branches.
After President McKay and the FIrst Presidency set me apart as a missionary to Nigeria (November 21, 1962), I asked them concerning interested persons over there who desired to become baptized members and were living in polygamy. President McKay told me to baptize and admit them into the Church. They could keep their wives and families that they had at the time of baptism but were not to engage further into this practice.