We used to do it with a Horn on large commercial grinder but we worked the power with a foot switch that allowed you to catch up. I've always said man should have been built with three hands.
You could have someone work the switch for you. Soak your casings overnite in a water bucket in the Fridge. They'll slide on and off the horn easier making for less stress tearing.
An option you have of not running it thru twice which sometimes will make you mush is cutting your Meat pieces the size of stew meat or smaller. Use a little Ice when you Mix your Seasonings and blend thoroughly. Then Grind and stuff.
You can catch it in the casing on the first pass with a Horn over a medium coarse or chili plate.
My favorite way to do it is grind with medium coarse plate into a lug, mix your seasonings, put it in Sausage Stuffer and start cranking.