i had a similar issue.

i had to melt out a stuck seat post, then my frame was left partially burnt with the decals slightly charred too. i liked the decals on the bike i did this too (it was mostly a pragmatic issue). so i was just going to get decals made or buy new decals.

but i didn't know if i ever wanted to sell the bike if i could get what the bike is likely worth (as a side note, it was a 3rensho... yeah i know. yeah i know).