riu has a good snorkle/sunset cruise to the cliffs(ricks) you have to book it asap,because it fills up fast. when they let you off at ricks go out the front gate,turn right and go to ltu pub for drinks & food (much better than ricks & will save you $$$$) then you can go back to ricks to see the cliff divers. maybe you can charter a boat with that many people,check negril onestop to charter a catamaran(booze cruise). good luck!