Citroen DS front wheel bearing questions


My SM has a rubbling front wheel bearing , so am going to swap in a hub I have had for years .
I would really like to give the bearing a service before it goes on the car so my questions are

1 does any body have the tool to take the hub apart , the manual has no relevent info on this subject
2 has anybody ever done this ,
3 should I just fit the " new " hub and hope.
4 there is a thread on AF about drilling into hub and installing a grease nipple , and I have considered doing this but , I and not sure how accurate you need to be to come out in the small ring between the bearing halves , it would be easy to break a drill bit off deep in the hub just by nicking the hard bearing with the drill.

Advice please .