You could maybe set your front koni's on the lowest perch and the rears on the highest perch to even out the stance.

Rear springs are usually shorter than the front springs. Also they usually have the coils closer together towards the top of the spring. The front coils are usually more evenly distributed throughout the spring, and they are longer.

Your springs are probably intalled correctly. I have heard that sportlines have a tendency to not give an even stance.