Acts 5:3-4 in saying that when one is lying to the Holy Spirit that one is also lying to God, it might not be conveying that the Holy Spirit is God, but instead that the Holy Spirit is a representative/intermediary of God. Hypothetically speaking, if God and angels exist, then if one lies to an angel (when the angel is acting as a messenger/representative of God) than lying to the angel might also amount to lying to God, since the presence of the angel would be acting as a means to communicate the person's words to God.
2 Corinthians 3:17-18 might not be saying that the Holy Spirit is God.the phrase of "Lord is the Spirit" might instead be saying that YWH/Jehovah is a spirit being, the great spirit. The phrase of "Spirit of the Lord" might be saying that the holy spirit (or Holy Spirit or Holy Ghost) belongs to God and comes from God, instead of saying it belongs to God. I believe such is the view of the WT and that view is the most reasonable interpretation to me of the what the scripture passage is saying in regards to the identity of the Spirit in the passage. [See the verses in the 1984 NWT, as well as John 4:24 and Isaiah 61:1 in the 1984 NWT.