Not to be a math nerd, but 6.5x8 is 52 miles. Half of it loaded with meat and gear. In Colorado, which means elevation and steep climbs and descents. This is beyond the capability of most people, myself included without risking injury or losing meat to spoilage. I am hunting in Idaho with my son this year. Our limit is 4 miles. And I know a guy who can help in a pinch. If you don’t 100% know you can do what you are proposing, don’t go down that road.
When I pack out, I’m doing a hindquarter per trip (sometimes with some trimmings in there too), the goody bag with a front, and a head with another front - 4 total trips, over 2 days, assuming permissive terrain, weather, etc.