Yeah, I’ve done that job. Not terribly difficult but tedious and time consuming.
You have to take the whole knuckle apart so you can replace the seals and the felt. The felt is just there as a kind of barrier to keep the debris off the seals so they last longer. Once the felt is gone the seals go next, then you have a leak.
Usually it puts a groove in the spindle that won’t seal unless you do something about that too. In my case I special ordered some spedee-sleeve type bushings to slip over the spindle to give the new seal a smooth surface to ride on.
The biggest part of the job is making sure you get all the paper shims back in the correct locations so that you don’t have to mess with the backlash in the gears.
Do you have the parts and service manuals? If not, take a look at my web site and you can download them from there. Do it quickly though, as my web site is about to disappear in a few weeks. www. harnerfarm.net