Can't answer for Amigo Tours, but most tours, taxis, etc. drop their passengers off at Pedro's. When facing the water, walk to the right and when you step into the sand (10 feet or so), you are on the Nude beach, and Club O property starts about 100 yards further. Look for the "Perch Bar" (first structure you come to), and if there is a line get in it for Happy Hour.
Your tour operator will probably meet you where they dropped you off.
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