I don't know how hard this is, but WinZip makes it so you can drop other files on a .zip and it will add them. Would it be possible to drop an lrc on an mp3 and have it run lrctool? I could see it interfering with other mp3 extensions and maybe not working right. That'd be easier than typing the names, but still a lot of D&D tedium.

Maybe I'll give File::Find a try and see how that approach goes.