Will the fix eliminate the FedEx and military planes at the terminal?
I don't know what you are referring to. There are no military planes or FedEx planes anywhere in the scenery, except the C5 Galaxy at the military area, which are of course correct, and they can also disabled with the YouControl menu.
Whatever planes you are seeing, are coming from the AI package you are using, and the parking spaces at KMEM are all already correctly divided between cargo and non-cargo areas so, there's nothing for us to fix.
But of course, regardless of the parking assignment in the scenery, if an AI needs to find a place to park, and the "proper" ones are already occupied, it WILL take any parking it will able to fit in.
The "fix" we were discussing here, it's just a slight tweak of some of the parking positions, that will have to be moved a bit backward to better fit the larger planes.