As I'm sure it will get mentioned to you for the correct term, kj's are using shocks with a coil spring as opposed to struts.
A big difference is any struts I've seen don't use an upper control arm, if a strut comes undone you have a major problem with how the car is driving as it's usually in place of a uca as well. There may be some that are an exception, but this is how I've seen it generally over all the years.
Copied directly from JBA's site for their kj control arms
"2002-2007 Lifted Jeep Liberty's works with lifts up to 4 inches"
"These arms are specifically designed to be used on vehicles with a spring, coil over or spacer lift"
So in theory with your spacer lift if it is giving you 3" of lift, you should be fine with the jba uppers and need nothing else, but I haven't done it to guarantee ya that but it seems like a solid start. Then as your stock suspension wears out, you can be saving up for some quality shocks and springs.
