I was looking for a pic of the installed lift to get a feel for the rake. Josh at IRO said the hub to fender is around 20.25 front and 20 rear and the spring rate is 200 inch/lbs. Slightly less rear lift and spring rate than the BDS or the OME coils. I'll be getting some Billy's and some good isolators form Kolak. I've read your comprehensive thread; it has tons of value and insight.
To the OP, I wouldn't add spacers, everyone on here that has says it rides like crap, even with the adjustable trac bar and extended sway links. Long arms are ideal at 4".
2003 WJ♦Inferno Red Limited(4.7 H.O., Vari-Lok axles)♦OME HD/BILLY 5100’S♦IRO t-case skid, adj. tb, sway links♦Moog SS♦Factory tow package w/harness & tow hooks♦ Amp/12” sub box♦new bad b**ch passenger♦1993 XJ country♦lift/muds/winchbumper-sold♦build thread instead of long A$$ sig soon...