SCUMM games have all their texts in the scripts. Other then decompiling them, there is scummtr, a translation tool which can extract all the texts in one file. The text file then has them in the order they are in the game resources, hence there is no obvious order. And it's not only subtitles, but any text the game can display somewhere, even debug messages.
Only the later SCUMM games like The Dig and Curse of Monkey Island have a translation file removing the need to edit the scripts itself.