Jaimie, thanks for your response. I guess ultimately what I'm wondering is whether I "need" them if I'm simply leveling out the front with the rear. I believe if I remember my measurements correctly, my front is about 1.5" higher than the rear on my Trail Boss.
I understand with some of these "leveling/lift" kits, that folks are also adding taller rear blocks and cranking their coilovers to the maximum 2.5-3 inches. In that case, I could see needing new upper control arms among other things I'm sure, which is why the BDS kit has so many components.
If I'm simply leveling out the front 1.5 inches, are they required (will my truck align just fine)?