2040 cal is really low for you, even to drop weight, try to stick 500 cals below maintenance if you want to have fat loss as well as let your body cope with the changes. Dropping too many cals will cause your body to respond by loweing your metabolism and thinking it is starving.
You have the ratio's right, and the 1g protein is a minimum thing, you can go up to 2g per lb bodyweight as long as you keep within your cals.
Just remember that not all carbs are the same, so try to stick to only complex carbs, rolled oats, sweet potato etc and you should be fine.
Post a sample diet here and we can help you to tweak it.