The First Year book was titled "Divine Authenticity of the Book of Mormon." You can see it here:
On page 43, the manual cites and quotes from Letter VII on the subject of Cumorah:
Oliver Cowdery was the first to give the world any account in detail of these early events connected with the coming forth of the great work of God. This he did in 1834-35 in a series of nine letters to the “Saints Messenger and Advocate,” published at Kirtland, Ohio, under the caption, “Early Scenes and Incidents in the Church.” And
as.these letters were published in the lifetime of the Prophet, with his sanction and in a periodical published by the Church, it cannot be doubted but that the statements contained in them are reliable....
The place where the Nephite record was deposited must and ever be of interest to those who believe that record to be true, and therefore a description of the hill of Cumorah will not be out of place in concluding this chapter.
[Letter VII on Cumorah]
The link is here: https://babel.hathitrust.org/cgi/pt?id=njp.32101074888171;view=1up;seq=45
The General Committee who prepared and published the manual included Rudger Clawson (ordained an Apostle in 1898 and President of the Quorum of the Twelve in 1921), David O. McKay (ordained an Apostle in 1906, Second Counselor in the First Presidency in 1934, and President of the Church in 1951), and Charles W. Nibley (who became Second Counselor in the First Presidency under President Heber J. Grant in 1925).
M2C intellectuals want you to believe that these men, along with the other General Authorities who approved the manual, misled the Church because they were ignorant speculators who needed to be corrected by Matt Roper, Jack Welch, John Sorenson, Tyler Griffin, Mark Alan Wright, Dan Peterson, and all the other M2C intellectuals at BYU/CES and Book of Mormon Central.