If you're going to the AN section, you can't wear a bottom. There may be topless options depending on where you are going.
As far as scarring goes, you would be in good company. Lots of people at the AN section have scars, stretch marks, etc. Geez - you should see the tats! Don't let that stop you - plus you can remain at a comfortable distance from others for most of the time.
My understanding is that the AN sections are "all nude," and a bikini bottom would not be allowed. However, I will say that while I realize you're likely quite uncomfortable with how you look with the scars, no one in the AN section is likely to say anything (although you may get asked what happened.) Having had our first AN experience when we went to Tower Isle in November, the feeling I got is that "people are people, and when you're nude what really matters is not what the outside looks like, but what the inside is like." I would suspect, as I said, you may get some glances, you may get some people asking what happened, but you won't get any "bad" reactions.
CTI first trip November 2011
CTI return visit May 2013!!
I've been to AN resorts here in PA and to CN, and nobody cares what scars you have. It may even be an ice breaker....Here in PA, someone had open heart surgery with a scar down the front. No one cared. All we care about is what's inside not outside.