Hi wbrantle, welcome to the forum. There's a wealth of information here to help you to excellent credit health.
I have 4 tax liens on my CR. 3 releases from 1994, and 2001, and one lien I'm still paying on. I've been afraid to even consider having the releases removed.
I know that doesn't answer your questions, but that's my experience. I know it is one whale of a chore to get it removed.
Perhaps someone who has, will chime in and give you their story.
Good luck.