Getting ready to put some work on my 2000 Excursion - starting off with shocks but am thinking about a lift. Nothing extreme, thinking about 2.5. I started hunting around and see that there are lifts and what folks seem to refer to as "leveler kits". Are they the same or is the leveler kit something that only gets done to the front?

Mine does sag a bit in the front and I was hoping to address that but am now a bit confused.

Anyone have any recommendations for what I am looking to do?

Looking to put something on there that is quality and does not kill the ride - also nothing extreme where I have to replace a lot of suspension parts to accomidate the lift.