craftgrrl | Once there were tucks....

Sorry for the text only post, but I promise pictures if this ever gets completed. :)

I'm making a Hermione Granger costume for Halloween, and the Hogwarts robes was the part giving me fits. Well, it occured to me to go get a graduation gown from a thrift store instead of trying out sewing skills that I don't have. LOL So I got my black gown and it's perfect except.... Is there an easy way to take the tucks out of the top part and re-sew the sleeves without screwing up the entire thing? I mean, I'm guessing I could seam rip where I want the tucks out, then stretch the material straight and sew it back on....but I'm scared I'm going to mess it up! Should I be scared? I just don't have the sewing experience/skills that most of you have, so if someone could just kind of reassure me that this would be ok to do, or tell me a good way to do it, I would soooooo appreciate it! I guess if I screw it up badly, I could go get another robe, because the thrift shop had tons of them, but I'd rather not waste the $7 again. :) Thanks crafty babes!