That’s pretty much the instructions for how to set them up for best use as far as the position of the spring eye bolt in the slider and the angle of the sliders themselves.
The bit about having the front spring eyes mounted narrower than the rears isn’t really relevant on A-bodies as the spring mounts aren’t designed that way. You could do it, but it would be a ton of work to accomplish that and having the springs set up that way has both pros and cons. E-body springs are set up that way from the factory.
