I was there memorial day weekend a couple (maybe 3..) years ago and it was not too bad. There's plenty of space in any case so I highly doubt you won't be able to find room. It is first come first serve though. The springs are liable to be a zoo but again, a couple of years ago they were not on that weekend. Nudity is no problem. Escpicailly when warm, I rarely wear a stitch from the time I arrive to the time I leave (though at night it does get chilly so I tend to put on some pants and heavy shirt).

Good Luck