That just never worked very accurately for me on any of the installs I have done. I have found this easier and very accurate. Install the unibody mount end, and with the jeep sitting in rest position, adjust the bar until the holes at the axle mount line up, then put the bolt through it (don't bolt it up or anything, just put the bolt through it). Take a yard stick or tape measure, put the end against the wall of the wheel well between the coil and the shock, and measure to an outer lug on the tire that will be easy to match on the opposite side. Take note of that distance. Do the same thing for the opposite, note that distance. Subtract the two distances, then divide that number by two. This is the amount the trackbar needs to be lengthened or shortened, depended when way the axle needs to move. Pull the bolt, adjust the trackbar so it is changed the amount you found in relation to the axle mount hole (measure center of trackbar bushing to center of axle mount hole). Have a friend sit in the drivers seat, unlock the steering but don't turn on the jeep, and have them turn the steering wheel until the holes line up, have them hold the wheel in place while you put the bolt through. Remeasure the wheel well to lug on both sides again to compare distances, and if it is within 1/4", that would only be a 1/8" adjustment, and that isn't a big deal, unless you want it dead on. Put the nut on the bolt and torque to factory specs.