Damn, you're right!
I picked up the vinyl the other day, but hadn't listened to it yet. After reading your post, I played it and, sure enough, the first chorus lyric is different! I compared it to all other appearances of the song in my collection, and I don't think this particular version has ever been released before. Looks like a screw-up to me!
I bet this version -- with the wrong chorus lyric -- was the way the song originally was finished. Then, afterward, Petty went back and replaced that first chorus with a copy of one of the later choruses (which all feature the "one more time to kill the pain" lyric) before releasing it.