It's a tiresome but worthwhile job.
When I got my Lemond TSX frame, somebody had 'repaired' a scratch on the seat stay by dribbling way too much matt yellow paint of the wrong shade all over the place. I used scratch remover to polish it off and it took days, but eventually I got it all off and got the original paint looking good.
Under all the gloopy mustard were a couple of very minor scratches that don't even go through to the metal, so to say the repair was worse than the damage is an understatement.
It'll be worth all the work in the end.