In the "History of Davidson Co, Tenn 1780 - 1880" by Prof. W. Clayton (1971) which I found in the book stacks at Tenn Archives in Nashville, I found the following: pg. 89 first justices by year commissioned included in 1813 Levi McCollum, and others. Maybe he is related to your McCollums. On a personal note, my g-grandfather, Levi McCollum Craft, was born in 1849 and died in 1929. I always wondered for whom he was named and I saw the above mention of a man named Levi McCollum. Its possible he was a neighbor of my Crafts and they named a son after him. I may find out one day!