Petter.......there is another member on the Commander forum that did a similar mod (my kit with a aftermarket spring)
He had installed the springs first and found that, although stiffer, the ride height had not changed.
I suspect the OME spring would have similar results.
You will have to search some......he posted before and after pics......was from Austrailia.


Holaday07 4.7.......your setup is a direct install............no surprises


Rob