1. Locate the car on level ground and measure the distance from the center of the rear wheel to the vertical edge of the fender lip for both sides. Roll the car back and forth a couple of times to settle the suspension before taking this measurement. Write these measurements down for future reference.
2. Jack the car up and place it on jack stands. It is important to get the car as level as possible, both front- to-back and side-to-side. Consult your owner's manual for proper jacking points. Do not jack the rear of the car up under the differential as is common with a solid axle. The Cobra IRS is not designed to support the weight of the car at this location. Failure to follow this warning can result in damage to the axle assembly.
3. Remove both rear wheel/tire assemblies.
4. Disconnect the bolt that secures the emergency brake cable to the lower control arm. This will make removal and installation of the springs easier.
5. Jack the lower control arm up slightly and disconnect the damper. Generally it is easier to perform this installation if the damper is completely removed.
6. Using the proper spring compressor, remove the rear springs. It may be necessary to disconnect the stabilizer bar in order to affect enough rotation in the control arm to remove the spring. There are other methods to remove the springs but not recommended for the novice mechanic.This can be a very dangerous procedure if not done correctly. If you do not know how to do this, have someone with the a requisite skills help you.
7. With the springs removed, re-install any suspension components you disconnected when removing the springs (except the damper).
8. The outer tie-rods must be replaced with the included billet aluminum adjusting collar and rod end. Before removing the outer tie-rod it is important to measure the distance the mounted outer tie-rod is from a fixed location, usually the exhaust hanger. Jack the lower control arm up until it is level along the lower rear edge. (Note the exact location you have placed your level for duplicating the procedure for the other side.)Figure 1
9. Using a tape measure or metal ruler, mark a location on the knuckle and note the measurement as well as the exact location of the tip of the ruler. You will use this reference point when re-assembling the system.Figure 2(installed kit shown)