Default [Q] Restore rooted 5110 to stock

I'd like to restore my 5110 to stock so I can update. I uses SU to unroot but that screwed something up because it's unrooted but still says it's "modified" and won't update. i believe I need to flash the stock ROM to get it un-screwed. All the sites I went to had some mombo jombo that took me to other sites, yadda yadda. Is there an ez way to do this? Thanks in advance.