Just till.
You'll leave a depression if you remove the sod.
You'll take the best topsoil away.
It won't work real good to try just scooping the sod away. Real uneven results, depending on your soil type.
Weed seeds tend to be in 5-10 inches deep from 100's of years ago, so while you will take away a lot of seeds, there will still be plenty waiting for you.
I understand where you want to get to, but - don't think it will really work out well.
Just till it until it's dead.
--->Paul