The main reason people recommend nail polish remover is because it contains acetone. Well, except for the nail polish remover that doesn't, but that wont work on the super glue.  ;D

Some acetone comes in plastic jugs and plastic squeeze bottles, but I believe those are Polyethylene based plastics and I'm thinking acetone may damage Polystyrene plastic found in models.

I would put a little on a small brush or q-tip and try on a sprue or underside of part. It will give you an idea of what kind of working time you have before it does major damage, which may be long enough for you to separate the parts.