Evidence of EL (eternal life/uncreated life) and Holy Spirit (God's Own Life) are not one in the same. On page 24, Vol. 1 we read,

“And Jehovah God formed man of dust from the ground, and breathed into his nostrils the breath of life; and man became a living soul” (Gen. 2.7 ASV). When God first created man He formed him of dust from the ground, and then breathed “the breath of life” into his nostrils. As soon as the breath of life, which became man’s spirit, came into contact with man’s body, the soul was produced. Hence the soul is the combination of man’s body and spirit. The Scriptures therefore call man “a living soul.” The breath of life became man’s spirit; that is, the principle of life within him. The Lord Jesus tells us “it is the spirit that gives life” (John 6.63). This breath of life comes from the Lord of Creation. However, we must not confuse man’s spirit with God’s Holy Spirit. The latter differs from our human spirit. Romans 8.16 demonstrates their difference by declaring that “it is the Spirit himself bearing witness with our spirit that we are children of God.” The original of the word “life” in “breath of life” is chay and is in the plural. This may refer to the fact that the inbreathing of God produced a twofold life, soulical and spiritual. When the inbreathing of God entered man’s body it became the spirit of man; but when the spirit reacted with the body the soul was produced. This explains the source of our spiritual and soulical lives. We must recognize, though, that this spirit is not God’s Own life (Holy Spirit), for “the breath of the Almighty gives me life” (Job 33.4). It is not the entrance of the uncreated life of God (eternal life) into man, neither is it that life of God (Holy Spirit) which we receive at regeneration (indwelling Holy Spirit). What we receive at new birth is God’s Own life (eternal life) as typified by the tree of life (eternal life). But our human spirit, though permanently existing, is void of “eternal life.”

How did I come to decide these words mean this? Go to page 34.

Prior to regeneration the spirit is separated from God’s life; only afterwards does the life of God and of the Holy Spirit dwell in our spirits. They then have been quickened to be instruments of the Holy Spirit.

Nee distinguishes between "life of God" and "Holy Spirit" so they are not the same; the life of God must refer to uncreated life/eternal life. And notice "God's Own life" typifies eternal life, otherwise he would not have said "God's Own life" as typified by the tree of life.

Careful reading will bear this out. Page 44, 45 are some additional examples.