Jose,
When you cross the equator at 0 degrees long by 0 degrees lat, you are a Royal Diamond Shellback. We did that on the USS Carl Vinson on its' 1983 World Cruise. I was one of the prime movers of the Pollywog Rebellion, and received an "S" in large print on my back for the ceremony (let's just use the phrase savage beatings). I deserved it though. On "Wog" day, we captured about 15 high ranking Shellbacks to pry where the Skull and Crossbones was hidden.
We used large sheets of canvas coated on one side with a couple of inches of grease. We rolled them up (in the greased side), hung them by their feet on the Mess Decks, and beat them with pieces of fire hose. We also poured oil in the tops, so it ran down into their noses. I understand it was horrible.
We never found the skull and crossbones. We found out later that it was hidden under the carpet in the XO's Stateroom. His personal Marine was a pollywog and tore his stateroom up. Didn't find a thing.
Best-Mike