If you have to disassemble the shaft you need to remove the end nut, these are normally peened or dot punched to lock the nut. Usually you need to grind or file the peening off but I managed to remove the nut from this one without doing that, I did need to clean the thread with a needle file after I removed it.

20190308_113316 by Paul Goat, on Flickr

Once the nut is removed you need to take great care removing the piston and shim stack. I use a screw driver pushed into the end of the rod and slide the whole assembly across and cable tie the end, obviouslly it is critical to keep all the shims in the correct order.

20190308_111914 by Paul Goat, on Flickr

You can now slide the seal head off and replace the seal if required. assembly of this part is just the reverse of taking it apart. I have a set of seal bullets to save damaging the seal on the thread when removing and installing. This is the only specialist suspension tool I have. I use Loctite on the nut and dot punch the thread nut interface in a couple of places for good measure.


20190308_112835 by Paul Goat, on Flickr