I wouldn't mix milk replacement with dry food, or canned food with dry food for that matter on a kitten that young. I've seen kittens inhale their food like normal thinking it's only mush only to half choke and gag on an expecting hard chunk. If you want to mix in dry food, I grind it down. They way they'll start to get the taste of it, without having to suddenly try to chomp down on a large piece of food.
How I wean my kittens is I mix Goats Milk (heated of course, and you can find the stuff in the milk section at Walmart) with baby Rice Cereal and Canned cat food. Do not use the chunks or shaved kind, you'll want something you can smooth into a consistent paste. The younger the babies, the more sloppy I make it. The older they get, I start to cut out the goats milk and cereal. Eventually you'll be left with feeding them just canned food. I personally don't like the kittens eating dry food until they are a good almost 7 weeks if I can help it. I have 7 week old kids right now, they chew on the dry if it's the only thing down, but they do much better on the canned food.
If you want to feed raw, which is good and everything, but again, I've seen too many young kittens gag on raw meat, even choke to death, because they were fed something they were not ready for. We feed raw at my mothers, heck our boys get full chicken legs, but the kittens do not get anything that isn't ran through the meat grinder first! And they don't start getting raw food until they are able to eat dry without issues. Bones I wouldn't do until they are much much older!