Part two. The rebuild...
There are a few things that you will need to have in order to be ready for the rebuild. Proper weight fork oil is the first. My fork uses 10 wt, and you will usually need just over one quart, damn! You may as well replace those seals and dust boots while you are in there. They are $40, and you will hate yourself if you change the oil, and later find a leak. FWIW, I have paid as much as $20/qt. for fork oil at the dealer, so I don't want to spill the liquid gold. The FSM for the bike which your fork came from will have some useful info. First is the spring free length. Next is the oil weight, and fill level. Finally is the correct factory suspension settings. These won't be correct for a KZ, but they give you a starting place. On to the rebuild.
Step 1) Put a film of new fork oil on the new seals and dust boots to facilitate their easy installation.
Step 2) Slip a plastic bag or some cling wrap over the end of the lower fork tube, and slide the new dust boot on the fork leg.
Step 3) Next is the circlip.
Step 4) Now install the seal just like the dust boot.
Sometimes there are steel or aluminum spacers that go in between the seal and dust boot, or on top of the seal.
Step 5) Now put the lower fork tube back into the upper, and work the seal down into its recess. I must note that on some forks, you will need to place the seal into the upper fork tube before you put the lower in. On these forks the seal is more of a press fit in the upper tube. You can use the old seal as a driver to carefully knock the new seal in place. Similar sized pvc pipe can also be used in lieu of a fork seal driver.
Step 6) Replace the circlip and then push the dust boot into place.
Step 7) Measure the free length of the spring. My FSM says minimum length is 10.5". Mine measured 10.7", so back in the hole they go.
Step 8) Start filling the oil. Don't worry about adjusting the level yet.
Step 9) Remove the trapped air pockets. You will need to pump the dampner up and down at least 10 times to properly fill it with oil. You will need to add some more oil at this point and repeat the dampner process until there are no bubbles coming out. Be careful to pump it slowly on the way up or you will have a volcano of oil shooting out. It helps to have something that will thread on the end of the dampner to help you grab it. It will bottom out about 2" below the tube, and will be oily and hard to hold. I drilled and tapped a piece of plastic for this purpose.
Step 10) Adjust the oil level. My FSM says that the oil should be 4.2" below the top tube with the spring removed. You can use a wooden dowel or a screwdriver as a dipstick. I like to put a piece of masking tape at the top of my dipstick. I'll stop the tape line level with the top of the fork. Just measure your oil level and adjust it to the factory spec. Don't overfill, as this will hydro-lock your fork and screw with the dampning.
Step 11) Replace the spring. Remember that the spring needs to be oriented just like it came out. Top and bottom are different.
Step 12) Get your helper ready again. Now replace the sleeve, and get your compressor out. Basically you need to reverse the process of removal. It's not quite as simple as the removal. You are balancing on the head of a pin at this point. Anyway, compress the spring, and pull the dampner up until you can get the retainer tool under the jamb nut again.
Step 13) Once you get there, you're home free. Screw the top cap back on the dampner, and tighten it down.
Step 14) Now use that compressor one last time and release that retainer. You will have to get the sleeve properly seated on the top cap.
Step 15) Screw the top cap back down and put the fork back in the triple clamps. Make sure to retun the preload and dampner setting to what they were before you tore the fork apart. However those dampner settings will likely feel stiff, since the oil is at the proper viscosity.
Step 16) Unscrew the top off of two (or more) beers. You deserve it. Job well done. You saved yourself some serious coin, and you may have learned a little about the inner workings of that motorcyling enigma known as the fork.