So, my jeep has a 4 inch lift.. I do not know what brand. I can get pictures of it tomorrow if you want to see it.. But, I'm curious to know if it would matter if i was going to install of of these http://www.rocky-road.com/xjbudget.html simply for a little bit more clearance and so my tires don't rub. I really need some more flex in the back and don't know how else to get without spending a lot of money

I know this is going to sound goofy, but have you disconnected you REAR sway bar? It increased my flex significantly, plus I trimmed and rolled my rear fender flares like Paul's and gave the tires a place to stuff, now I have no rear flex issues (shut up Bob).

Here's a pretty decent flex shot that shows front and rear articulation:



shot from the Collateral Damage run, by the way, and here's the thread, not just the write up...

I'm running 35's, 6" lift, but disconnecting the rear sway bar (thanks Geoff) made a big difference in rear flex (shut up Jack).

I actually don't have one on my jeep at all. Didn't have one when I bought it. I have my fenders cut to the rivits but my front can flex like no other, but the rear flex is just not good at all. there isn't very much room at all until it his the bumpstop.

Do you have the overload leafs in your rear leaf pack? Alot of folks remove those and sub in a small block in it's place. It will reduce your payload but if you don't tow with it it won't matter much.
In my case i went with a longer and flater leaf pack. It allows for alot of droop and it will stuff the tire into the well until it rubs the frame (who needs bumpstops, lol). The longer pack required relocating the rear shackle.
Just some thoughts.