Rather than scrape the paint off, add fibreglass, coat it, sand it fair, re-coat it and the surrounding wood and then repaint, why not simply drill oversize holes, lay the yard down with the holes vertical, put masking tape across the lower part, fill with thickened epoxy (preferably mixed with graphite powder), let it harden and then drill out to correct thickness. Alternatively a greased stick of some sort - pencil? - slightly larger than the intended rope, could be stood up in the thickened epoxy until it has gone off. A lot less work and probably even more effective against the grain splitting.
The yard on
Fantail actually started out life as a yard on a square rigger, before becoming a mast on a 40+ ft yacht and finally ending up as a yard once more. The wood must be pushing 100 years old and the grain is incredibly close together. Makes the gorgeous stuff I've bought for SibLim's mast look pretty rough in comparison!