I recently took an old guitar (1969) to my luthier. He was going to work on the buzz near the nut on the 4th string and remove some tap plate adhesive near the sound hole, also work on some dings on the top.
He managed to take the buzz out and the excess glue is totally gone.
The largest ding on the top was filled and buffed with some kind of spot laquer and looks great! You can still see the mark beneath the finish, but the repair is totally flush to the original finish.
I asked him how he did that, but he was reluctant to answer (he started speaking in his native language).
What's this secret? and can i do this myself?