Ok Squeeker
It is simple really
If you undo one of the nuts the wheel will come off (don't drop the 2 washers one either side of the wheel they are important)
Lay the wheel on its side and carefully drift the opposite bearing out (the bottom one ) it should come out easy just be sure to use the drift/screwdriver on the center of the bearing not the soft shields as they bend easy
You will now find a small bit of tube that goes between the bearings to keep the centers apart (this is too long and needs shortening by about 1/2 a mm)
Put the tube in the chuck of the pillar drill with just a little bit sticking out (don't overtighten it as you will crush the tube )
Set the table an inch or so below the chuck and stick a bit of fine emery paper on the table
You can now start the drill and lower it untill it is lightly touching the paper
Keep the paper moving sliding it back and forth so it evenly grinds the end of the tube
Do this untill the tube is square on that end (only takes a short time) then reverse the tube in the chuck so the other end sticks out and repeat
It is then a case of trying it in the skate and taking a bit off each time until it fits right
A set of digital calipers helps so you can measure it to get a good fit but it can be done withyout just takes longer
It is a lot easier to show than explain but hopefully that should be clear if not ask about the bits that are confusing
Jason