phi910,
Nudity is allowed anywhere you do not get a complaint. Deep creek (not just the springs area) is historicly know as a nude area. There for there is no restriction (except 14 miles up stream from the springs at the t-6 crossing), In the San Bernardino National Forest. Unless by county law you get a complaint from a citizen who agrees to go to court. So keep people happy by being considerate.
Back years ago I spent 8 days camping on the Bowen Ranch going to the springs daily and never wore a stitch. The weather was 80 degrees during the day. 70 degrees at night and a full moon in more ways than one.
Use common sense rules and respect people's wishes. And have fun at this bastion of freedom called Deep Creek hot springs.
Enjoy your new found freedom, wish I were there ;-)