Your link doesn't work. Put your pics on photobucket and copy and paste the image code in the message window. Measure your springs, surely somewhere around here there's a chart that tells the different spring lengths for JK's. At least with the spring measurements someone with the same size lift can tell you what you have.
Flex it out and see what hits and how badly...
If the tires are just barely hitting the rear fenders, I'd say it's about 3.5" and I'd just add flat fenders. If you're pounding something, maybe start over.
You really don't have to put a JK into the sky for biggish tires. My friend has 40s and is running only 5.5" lift with FFs.
2 door or 4 door, btw? How are the driveshaft angles looking?
yeah, I'd say 4" too. I'm at 3 on 35's and didn't get it to rub anywhere. I'd toss a 1.5" BL on that and call it a day. the gap between the tire and fender looks good enough except for the most intense rock trails. a BL is cheap and will take care of that though.
what other mods is are done. a 2 door needs some new driveshafts with alot of lift. hell I'm only at +3 and my front shaft is thinking about bombing. one other thing is if that's a Sport or X, the front D30 needs to be watched, modified, or swapped. I'm nervous with 35's on it and might weld it up, let alone 37's. just be careful with it and if it breaks shafts or those C's, you'll need to downgrade to 35's or find a 44. take off's from folks moving to 1-tons can be had for $1000 plus a re-gear. not bad, and they are usually locked. just wire her up, flash the PCM, and rock and roll.