Yes
I'm using 4 front and 4 back. It helps a lot with the weight but I have to jack the rear up to engage/disengage them.
I'm going to drop to 3 to be able to engage w/o jacking the rear.
For installation, the trick to get the long bolt through the hole in the spring is to use a floor jack under the leaf spring mount and jack it up there, you will be able to easily drop the bolt through.