Just depends on how high up on the wall you want the Bull, and what pose you want. You can get away with a lot or you can maximize the pose with high ceilings. If you were planning on 10' celings, I would consider 12". If you have a space for a vaulted ceiling, even better yet. Most importantly are you leaving room for a Moose, Big Horn Sheep, Mountain Goat, Caribou, multiple deer, antelope, etc. Think long term. Congrats on a beautiful bull