Jpaye

I just got my JK, 2007. It already has the suspension lift and it appears to be a 4" and 35x13.50 Toyo's. My questions are first, is there a way to tell what size the lift is? 2nd, I know with the F150 I just got rid of you can install a leveling kit and the suspension lift to give a little more lift, so my question is can I stack the spacers on top of the coil spring with the suspension lift and be okay? Will anything else need to changed as far as shocks or anything?

Thanks for the help

Also what is the best leveling kit to purchase and from where?