Getting to this thread a little late but wanted to comment on mixiing spices.
I always add the spices after the second grind but I do one other thing.
I put some water in my blender and then add the spices to the blender.
Blend everything up which dissolves the salt and then pour the mixture over the meat.
It makes for a very uniform distribution of seasoning in the meat and the water also makes pumping with the stuffer a little easier.
I remember my grandfather always adding some water to his meat to make the stuffing easier.
I prick any air pockets the sausage prior to hanging and smoking.
The added water will all go away when the meat is being smoked.