I've done a couple of racks...not all that difficult, but there are some things to keep in mind:
Be very careful not to ding the polished portion of the rack cylinder (solid tube that slides back and forth, with tie-rods attached to each end)...particularly on the right (passenger) side beyond where the toothed (rack) portion ends. Also, this polished section can, over time and/or if run dry while not adequately lubed...become corroded/scratched up enough to leak past new seals. Re-polishing is possible to a point.
Also be aware of the proper orientation of the steering shaft input on the upper rack tower before you remove it. There is what appears to be a witness mark (small arrow) in the casting of the upper rack tower, which points directly at the milled flat of the splined rack tower shaft when this has been correctly reassembled...making sure the rack itself is centered by checking the centration of the machined "dimple" (which allows the rack to be locked in its centered position) in the lower inspection port, accessible by removing the threaded plastic plug. (I did a double check of this orientation by rotating my cars steering wheel to its locked position and then inserting the lower shaft to tower (splined connection) lock screw, then mapping the lock screw's orientation and matching this with the orientation of the aforementioned milled flat). At any rate...look carefully at this photo and you'll see the "witness mark" pointing at the milled flat:
And be very careful when removing and replacing the inner tower seal. Some say to carefully pry the old one out with a screwdriver...but I found that a pilot bearing puller worked perfectly here - with its arms spread enough to bite into the old seal, but not so wide that it marred the aluminum walls on the tower:
After the puller was inserted into the old seal, I put the assembly in a vise, installed a bolt into the threaded part of the puller, grabbed the upper part of the bolt with a vice-grip, and carefully pounded the vice grip upward:
Finally, make sure not to mix up your crush washers! I did this on my rack, resulting in a shower of ATF on my garage floor, and my having to extract the rack once more...which also meant having to undo tie rod ends and stablizer bar assembly. Not fun!