Sounds about right.
It will benefit from thicker spacers on the rear, to make the front and read tracks closer to equal. This is a win both aesthetically and for handling.
I recall most people aiming for an extra 7mm on each side of the rear (compared to the front), but I also recall going a fair bit more than that on the rear of my 244 rally car.
Be aware that the wagons have a slightly wider diff, so the “best” rear spacers are a smidge narrower than they would on a sedan.
Your willingness to cut/fold the lip on the rear wheel arches is also important to the decision making process.
