You are correct, I was speaking off the top of my head. The real date that blacks in America were allowed full membership into the Mormon church was 1978. Did a simple search and came up with these quotes.
LDS - "...[T]hrough their INDIFFERENCE or LACK OF INTEGRITY TO RIGHTEOUSNESS, [blacks] rendered themselves UNWORTHY of the Priesthood and its powers...." LDS "Historian" B. H. Roberts, The Contributor, vol. 6, pp. 296-297
A CURSE ON THE "SEED OF CAIN" ?
LDS - "You see some classes of the human family that are BLACK, UNCOUTH, UNCOMELY, DISAGREEABLE and LOW in their habits, WILD, and seemingly DEPRIVED OF NEARLY ALL THE BLESSINGS OF THE INTELLIGENCE that is generally bestowed upon mankind. The first man that committed the odious crime of killing one of his brethren will be cursed the longest of any one of the children of Adam. Cain slew his brother. Cain might have been KILLED, and THAT WOULD HAVE PUT A TERMINATION TO THAT LINE OF HUMAN BEINGS. This was not to be, and the Lord put A MARK upon him, which is THE FLAT NOSE AND BLACK SKIN. Trace mankind down to after the flood, and then another curse is pronounced upon the same race -- that they should be the "servants of servants;" and they will be, until that curse is removed; and the Abolitionists cannot help it, nor in the least alter that decree." LDS "Prophet" Brigham Young, Journal of Discourses, Vol. 7, p. 290, 1859, emphasis added.
LDS - "Though he was a rebel and an ASSOCIATE OF LUCIFER IN PRE-EXISTENCE, ...Cain managed to attain the privilege of mortal birth.... [H]e came out in open rebellion, fought God, worshiped Lucifer, and slew Abel.... AS A RESULT OF HIS REBELLION, CAIN WAS CURSED WITH A DARK SKIN; HE BECAME THE FATHER OF THE NEGROES, and THOSE SPIRITS WHO ARE NOT WORTHY to receive the priesthood are born through his lineage." LDS "Apostle" Bruce McConkie, Mormon Doctrine, pp. 108-109, 1966 edition, emphasis added.
LDS - "The gospel message of salvation is NOT CARRIED AFFIRMATIVELY TO THEM [blacks]...." LDS "Apostle" Bruce McConkie, Mormon Doctrine, p. 527, 1966 edition, emphasis added.
LDS - "...[W]orthy males of all races can now receive the Melchizedek Priesthood.... It means that members of all races may now be married in the temple, although INTERRACIAL MARRIAGES ARE DISCOURAGED by the Brethren...." LDS "Apostle" Bruce McConkie, Mormon Doctrine, pp. 526-528, 1979 printing of 1966 edition.
Note: Mormonism grudgingly allowed blacks to enter its priesthood in 1978. But notice the continuing racial prejudice, even as the group attempts to declare that blacks are now acceptable!
And so on, and so on. The point is, a black man is now good enough to help BYU attain greater glory on their sports teams, the cross team is especially blaring, but at the same time, is seen as a "mongrell with unclean seed, that is strongly discouraged from breeding with the church's sons and daughters." This is actually fun to read, because this is still the view held behind the "white curtain." Members on the scrolls deny all you want, but these are quotes from your own leaders. Just your history for the day folks. Zieg Hail!