Ok since Icon's rear spring is 2" lift and Sway-a-way provides 1.5" lift, does that mean that Icon will yield 4" of lift and sway-a-way yield 3" of lift? Kinda like how the spacers are.
Also, if you were to measure before and after installation, your results may vary depending on the condition of your stock springs.
ie, if your butt's sagging due to worn springs, and you replace with 2" lift springs, the apparent results will be >2" (back up to stock height plus 2").