I've asked around and read a lot about this. Many say that 2" or more poses a risk to CV's. Others claim to run this way for years with no problems. Now some people say they have 2" of lift and what they have is 1.5" spacers. Then there are the kits with 2-3" of lift with longer springs and struts, some come with shock or remounting brackets for them and drop brackets for the CV angle, longer struts, new arms, spacers and all sorts of variations. But you're spending $700 plus for these.
Sounds like you want 31's to fit. From all I've heard you can fit 30's with 1.5" coil spacer lift with maybe a little fender trimming. 1.5" spacers + 2" body lift will fit 31's no problem. Sounds like you are going cheap, that might be the best bet. I've also seen people fit 31s and bigger on 1.5" spacers only with a lot of fender and wheel well banging, and trimming. If your body isn't great this might be a cheap option. A 2" body lift is about $100 or can be home made.
Tire sizes vary about an inch in worst cases also. So some 235's and 30's are about the same. Many 31 inch tires are more like 30 -1/2-3/4. If you have tires already that's something to consider.
I bought Daytsar 1 3/4 jeep spacers, ( $100 ) these particular ones are supposed to fit with no mods. They are actually very close to 2" but may squish down a bit. And I may shave some off the front to even things since you get more lift in the front with the same spacer.
It may be wise to get the 1.5" - 2" spacers and the tires you want, and then if you get too much rubbing, spend $100 on the body lift. They say it's easy and takes a couple hours? I guess your shifters get shorter but are OK. And Rocky Road sells them with extensions I guess.
At this time I'm going 30 x 9.5 dia. tire only which is about a 29 3/4 inch diameter max. Big improvement over my tiny 215's which are under 26" now with wear. I'm hoping to clear with minor trimming. This gives me a pretty decent trail rig, about 3-4" higher on the frame, and 1.5" or so more at the diff. heck I can take most trails here stock as it is driving sensibly with good lines. If you want to Rock Crawl or do serious Rubicon type stuff, you probably have to part with a few grand in mods to do it right. 6" lift and sliders and stuff. Anyway, just some things I was thinking about.