I do become influenced, but I go ahead anyway and then when I do another draft, I re-write it. Then it becomes more my own style.
I would say that if you feel you are imitating, go ahead anyway. It's a way of learning.
Then later you can go back over it and re-write in the areas where it seems to you that you've been too imitative.
But McCarthy certainly taught me to write narrative summary and Dickens taught me description.
Where in America is your Civil War story taking place?
I was lucky to escape from Raintree County with my sanity; I sneaked out the time portal when one of the many flashbacks ran headlong into a flashforward.