Welcome
@Jackass22
many opinions will be offered. There are some considerations, like what size tire, use, and if you are ok with trimming fender wheel openings. on a K20 I run 4" shackle flip with 56" 1 ton spring and 6" shackles, probably little more than 4" in the rear, 4" tuff country hd in the front. Stock steer configuration. Rides very well in the rear the front can be a bit rattly, airing down the tires help a lot here.
I prefer the poly, and am using the ORD Kevlar bushings. Nothing wrong with rubber in good shape, it cushions better than poly.
If money is not an issue get the ord custom leaf springs for your truck at the ride height you want, Cadillac of springs