Is this for an XD?
I have seen tons of posts complaining about how hard XD sights are to remove. MANY people have scratched up their slide doing it, and even some have had their gunsmith mess up the slide finish when they were trying it.
Take it to someone who knows how to do it. Sometimes, there is some filing involved - not fitting correctly or 1 sight needs to be a bit shorter, etc.
Go pay the $20 to a local smith and have it done right. Just my 2 cents...