Question:
Would you be so kind as to provide me with cross-references and clarity linking Isaiah 41:10 [1] "...I will uphold thee with the right hand of my righteous", and Isaiah 41:13 [2], "For I the Lord thy God will hold thy right hand,..." [KJV] I noted in the NAB that wording was changed and in so doing lost the meaning believed to appear within these verses.

Answer:
In this section of Isaiah, God is encouraging and comforting Israel from the fear of all of their enemies. He is assuring them that He will hold up their right hand by His righteous right hand. The right hand is the representative of power and authority. So God is saying that God's righteous power and authority will move through their right hand to defeat their enemies. Here is the literal translation of the Hebrew of Isaiah 41:10 [3] and Isaiah 41:13 [4]:

Isaiah 41:10 [5]
Do not fear because I am with you. Do not be afraid because I am your God. I will strengthen you, I also will help you, I also will take hold of you in the right hand of My righteousness.

Isaiah 41:13 [6]
Because I am Yahweh your God, I will take hold of your right hand, I the One saying to you, "Do not fear, I will help you."