After we changed some of the original halyards to Dyneema we noticed the
halyards started to wear off the anodizing on the mast. To prevent this
we bought rope terminals and fitted them to the mast. Since the openings
were not prepared for rope terminals we had to do some filing and remove
material. This was easiest done with a electrical drill and a rotating
file (burr). We carried out this work with the mast standing on the deck
which took extra time as we had to use ladders and climbing harnesses.
Our recommendation is to do the job with the mast down. Protect the
areas close to the hole with some heavy cardboard or similar and if
possible, use a router as it allows you do the work more accurately.
Don't forget to use protective glasses and gloves!