I believe it is important to pay attention to the little words. Sometimes they say a lot more than their size would indicate. Christ is the "...head of the body..." and "...head over everything..."
Did you catch it? Did you hear the two different little words? Does it make a difference?
I recently read this, "God created man to be head over the woman..."
That's not what the Bible says. The Bible says that man is the "head of" the woman.
"Of" and "over". So what! Does it really make a difference?
The Full Rights of Sons, Chapter IX: The Head Over Everything - "You Have Only One Master."