Carnitas is nothing like above.
You need a big kettle, and oil (penaut oil, or better rendered lard) you put it outside on a burner, bring the temperature up to 300 degrees.
The meat is traditionally big chunks (later you will cut in to small pieces hence the diminutive name carnitas) and you fry them for about 3 hrs. (nobody talks about internal temps) and they will be ready when they start falling of the bone.
In Mexico they use the entire pig.
But in USA is more accomodating to use the shoulder.
Half way thru the cook you can add a little milk and sliced oranges.
Hope this helps