Did you get any driveline vibration on the rear?
i got a 6" fabtech with longer trailing arms and needed a 2" coil spacer to be level with my 7" FTS front kit. I am noticing some vibrations at 40 mph only and think its due to pinion angle off axle not match angle off tranny. I noticed Zone and BDS use adjustable upper trailing arms which would allow to have the correct angles. So wasn't sure what angles you have or how they were set but interested to see what or if any vibrations you have with this kit.