Isaiah 6:8 (King James Bible) also I heard the voice of the Lord saying …
Here in the printer’s manuscript, Oliver Cowdery initially wrote “and I heard the voice of the Lord”, where the and was written as an ampersand; then almost immediately Oliver wrote also right above the ampersand, but only later did he cross out the ampersand itself. The level of ink flow for also looks unchanged, but the crossout of the ampersand was done with a broader quill and shows a heavier ink flow. This difference suggests that some time elapsed after Oliver wrote the ampersand and the supralinear also before he decided to cross out the ampersand. Perhaps the crossout was done when Oliver was proofing 𝓟 against 𝓞. Most probably, the corrected reading in 2 Nephi 16:8 (also rather than and ) represents the reading of the original manuscript rather than a correction based on referencing a King James Bible. The vast majority of minor differences between the Book of Mormon text for 2 Nephi 12–24 and the corresponding Isaiah passage (Isaiah 2–14) were left unchanged.
Furthermore, there would have been nothing strange about the initial and of “and (also) I heard the voice of the Lord” that would have motivated Oliver to consult a Bible. David Calabro points out (personal communication) that the original Hebrew here actually has and rather than also. Even so, it seems highly unlikely that the original manuscript had the Hebrew and rather than also. The initial introduction of the and in 𝓟 seems to be simply the result of Oliver’s expectation. Elsewhere in this long King James quotation from Isaiah 2–14, there are 241 clauses that begin with and (an average of almost one every verse), but only one clause begins with also— namely, here in 2 Nephi 16:8 (which implies that the King James translators would have been more consistent to have translated the Hebrew and as and and not as also). In any event, the original Book of Mormon text appears to have followed the King James also here in 2 Nephi 16:8.
Summary: Maintain in 2 Nephi 16:8 the corrected reading in 𝓟 (“also I heard the voice of the Lord”), which agrees with the corresponding King James reading.