Chad, the old fur-buyer I worked for taught me to tap the coons on the head to stun them....Then hold them up by a back leg. Swing your bat angled-in down the spine and make contact about 2-3" from where the spine meets the skull. This will separate all connections to the head and is very humane. Also minimizes the blood clots on the head which hinder skinning and scraping later on....plus keeps your trap site clear of unwanted blood.
You can also stun them and wrap them around an 8-12" tree a good one and that will separate the spine.