I am still awaiting a couple of tools so I haven't fully dismantled mine yet but the manual is attached to this post. I think you will be able to download it directly but if not contact me and I'll P.M. you a copy. I assume this is the old type Champion you are talking about the new one is quite different
To get to the bearing adjuster do the following :
Move the motor as if you were changing speed and slip the belt off
Hold the pulley and remove the castle nut on top of it (you can either use the belt as a kind of spanner or pop something in the spindle taper and hold that) It shouldn't be particularly tight mine wasn't, a few gentle taps with a soft headed punch should loosen it or a 'C' spanner if you have a suitable one
Remove the pulley. either with a bearing puller or a couple of big screwdrivers it might be a bit tight on the keyway but luckily on this one it's steel not aluminium so you can apply a fair bit of force without damaging it.
remove the 3 capscrews from the casting below and lift this out this will remove the spindle drive bearing assembly which can be dismantled in the usual way if required, note that one of the bearings is held in by big circlips so you will need some solid circlip pliers (one of the tools I;m waiting for I didn't have any internal ones big enough)
Below this you should find the bearing adjusting nut as in the above picture and it's dreaded tab washer you will need to clean some of the black grease away to see it and a strong light is required, I used the mill's own worklight very handy !
lock the quill, in it's highest position and hold the spindle to stop it rotating, I put a large drill in the taper and clamped it gently to two pieces of wood held in the machine vice, loosen the vice clamping bolts to stop it putting to much side thrust of the spindle.
The tab washer can now be knocked down with a small pin punch and the adjusting nut should now be able to be tapped round again with a soft punch.
If you have stripped motorcycle gearboxes most of this will be "old hat" to you and not particularly difficult, Bike boxes are much more tricky than this, they have a nasty habit of simply exploding in a cloud of gears and springs and stuff when you split them.
I haven't dismantled one of these before either so we will both be on the same learning curve, The exploded views in the manual although not particularly detailed or descriptive are of help though
The next stage is to try to get the quill out I shall keep you all informed on progress.
Best Regards Mark