Instead of the RE I'd call these guys Rokmen - Off Road
and tell them what you want to do, they'll set you up right. I probably wouldn't go 4.5 inches either, 4" max.
I'm working on a similar setup but going to 35's. That RE kit is leaving out a lot of stuff that you WILL NEED as in, not optional. About $500 worth. Further, those aren't the best quality arms.
Personally, I'd do something like the 2.5in OME ultimate kit from Old Man Emu Ultimate TJ/LJ Wrangler Kit | dpgoffroad.com
or ask for something similar from rokmen which will get you on 33's. Then, if you still want better from there, you'll want to load up on currie/savvy/rokmen control arms and go with a tummy tuck, SYE and Cardan shaft.
At that point you'll be sitting on around 3.75in lift (2.5spring + 1.25 BL), with 2 inches more ground clearance undearneath by losing the shovel and can add on rokmen's other armor pieces for the oil pan, etc.
If you want more lift at that point, all (purchase wise) you need to do is add new 4" springs, longer shocks and get the length of the drive shaft adjusted (about $150). But that's not necessary at all for any trail really, just personal pref.