Jenn, you are so brave!!
You could wear one of those wrap dresses and if it feels more appropriate to keep it on when you get there, you can, but if you feel like you need to be like the 'romans', you could unwrap the wrap dress and take it off, which would seem like a robe at that point. You'll only have one piece to remove rather than a shirt, pants etc.. and it will look like you planned it. After all, you'll have to wear something while you're driving there. Otherwise, it could make for a very interesting traffic stop should you get pulled over. lol