I ordered the 2001 Chevy lowering shackels (1 set.) Is this all I need to lift the rear of the D? Just the one set of Shackles? They go on the end of the leaf spring closest to the rear correct? Any tips/suggestions would be great. I just soak in WD40 for a week, jack up by the frame and start unbolting? I thought I read something about putting a bottle jack between the frame and the spring? Is this neccessary? This will lift the rear about 1.75" correct? Sorry I'm full of questions!! Thanks in advance.