I have adjustable spring plates onmine. I bought a set and added some extra welding to make them stronger. The hard work is usually taking the stock ones off because they might be preloaded such that they are against the stops when you car is lifted, they can hurt you. If you place a jack underneath or use the special tool, then you're ok and it is relatively easy. Installin is easy. I threaded the adjusters 1/2 way and installed the plates such that the lower plate edge coincided with the stop and then installed new rubber bushings. Oh yeah, use longer bolts and 3 10-mm washers to make up for the plate thickness. If you do not, you'll crush the outer rubber and distorted. I love the adjustability!! I hope this helps you and others. I'll post pics too.
Regards,
Tony
speedy57tub
lvwoodgod