this write up is from altimas.net
Instructions credited to Altimat.
First you need to get the car off the ground. If you don't have a floor jack and jackstands, the Nissan jack will work - one corner at a time!
Tools needed:
Jack and 1-4 Jackstands
Rental Strut Spring Compressor ($9.50 for 4 hours)
14, 17, 19 mm Sockets, Ratchet, 3" Extension
17, 19mm Wrench
Flat Screwdriver
Lug Wrench
I have to recommend using a torque wrench and factory torque specifications during reassembly(I didn't). There also appeared to be some thread lock on the suspension bolt threads so you may also want to pick up some thread locker and apply a few drops to each fastener during reassembly(I did). Please be careful so you don't hurt yourself and have to sue me!
Front first - remove the brake line clip with a flat screw driver and a bump from your palm. Remove the brake line from the bracket. Remove the ABS sensor wire from the two holders if present. Remove the 2 large 19mm nuts from the lower strut bolts (17mm heads), then remove the bolts.
Now remove the sway bar link. Hold the hex on the back side while removing the nut.
Loosen the top center strut bolt (do not remove). Support the suspension with a floor jack, or have your helper support it while you remove the three upper 14 mm nuts. (these are under your hood)
The struts will fall right out.
The next step is to swap the springs on the struts. I used a rental spring compressor and followed the instructions included. Alternatively, you could bring the struts to a shop and have the springs changed for a nominal fee.
If you elect to do it yourself, clamp the springs with the compressor. I was only able to grab one coil spacing due to the lack of coils on the OEM spring, and the threads on the compressor bottomed out before the spring pulled away from it's perches, however, there are plenty of threads on the upper strut nut and tension was fully released before the nut was off. Remove the upper nut, upper mount and gray washer thingy. Replace the OEM spring with the Eibach, which only fits one way. Align the notches top and bottom, and reinstallation is the reverse of removal, except that you don't need the compressor. One person applying pressure to the assembly while another starts the nut worked for me. Just snug the nut for now, it can be fully tightened after installation. The upper mount holes are assymetrically spaced to insure proper positioning during reinstallation. There is a thin gasket between the strut mount and body that remained stuck to the body on my car.
The rear couldn't be any easier!
First support the lower control arm (do not lift it, just support it) as shown. Then remove one bolt - 19mm nut and 17mm bolt head same as the front lower strut bolts. Then lower the jack and the lower arm will drop. Pull out the jack, and push the lower control arm down even farther to remove the spring and the upper and lower bushings.
And slip in the Eibach!...but first, reinstall the upper bushing. Crawl under and you'll see some metal tabs in the upper perch that engage slots in the bushing. Place them over the tabs and then turn them 1/8 turn and they'll hang there. Reinstall the lower bushing lining up the notch. Place the spring into position (with the labeling right-side-up!) on the upper bushing, and rotate it to align the lower end of the spring with the recessed notch in the perch. The top is not notched.
Then lift the arm up with the floor jack to align the bolt hole. Reinstalling the bolt effortlessly requires that the lower arm be twisted slightly. I inserted a 1/2" breaker bar horizontally through the two large holes near the outer end of the lower control arm to twist it in the right direction. I assumed that this is why those holes were there!