Honestly, it's very time consuming work.
you should stripping current paint in order to look decent paint job.
it might take more than 6 hours to stripping paint and you have to be very patient.
if you don't want this process. you should just change grommets.
these links are my PJ process.
http://tt.tennis-warehouse.com/showthread.php?t=357115
http://tt.tennis-warehouse.com/showthread.php?t=361608