I have an 86 sierra with a 17 year old spring 2" lift kit. I did the ord shackle flip kit with super shackles and kept the rear lift springs and did new 6" front springs. Not done building project but i was amazed that the rear is sitting level with ftont end . When the motor goes in, the front will be alittle lower. ( i think it looks better than the backend sagging). So I myself like the shackle kits
Just my 2 cents
Would like to see photos when u are done
Jd