You most likely have SS springs. But I'd verify that by checking the length of the front hanger. Also, are your shocks long enough to be compatible with the extra arch of the spring pack? If they are too short and bottomed out at the end of their travel, ride quality will suffer.

You can take a leaf or two out of the pack to soften them up and maybe get a little less arch in them. Costs nothing but time to try this.