I am going 4" lift on my '85 Blazer. What needs to be done to make sure I have no vibrations I have heard about? Will I have to go slip yoke shaft? Can I get away withg a 4" and no vibe? Mark 1985 K5 Built 330HP crate 350, SM465, NP208, 10 bolts, Ranchos and 31X10.5 on Rallys!