front axle pivot seals on a B6000 4wd

[artfull dodger]

How hard is it to replace the swivel seals on the front end of a 4wd Kubota B6000? both of mine are leaking when she sits for any length of time. Unknown hours on the machine, but its a 1975 model year, so they are well due for replacement. I am fairly good at wrenchin but never tackled this kind of project before. Thanks Mike and Michele T