I TAKE NO CREDIT FOR THIS SOLUTION. It can be found here:
http://uk.ign.com/wikis/metal-gear-solid-5-ground-zeroes/Cas...There are seven of Chico's cassette tapes that you can find throughout the various missions of Metal Gear Solid V: Ground Zeroes (to clarify, they cannot all be found in a single mission). Each one contains information surrounding the events of MGS Peace Walker, Ground Zeroes and The Phantom Pain. Certain tape locations can usually be uncovered by interrogating a random guard in each mission.
Note: If the trophy doesn't unlock when you get the last tape, finish the mission you are on and it should unlock after it is finished.
Chico's Cassette Tape 1: Awarded for completing "Intel Operative Rescue" Side Op.
Chico's Cassette Tape 2: Ground Zeroes mission. Found in the central watch tower at the Administration Building.
Chico's Cassette Tape 3: Aquired through the course of the Ground Zeroes Mission. It is given to Snake by Chico after he rescues him from his cell and brings him to the cliffside cave.
Chico's Cassette Tape 4: Rescue the P.O.W. to be executed in the Ground Zeroes mission. He can be found in the West Refugee Camp.
Chico's Cassette Tape 5: Ground Zeroes mission. Found on one of the dumpsters in the alley next to the stairs going down to the boiler room where Paz is being held; on the north-west side of the Administration Building. This must be done before you rescue Chico or Paz.
Chico's Cassette Tape 6: Eliminate the Renegade Threat Side Op. Found in the armory building closest to the starting point of the Ground Zeroes mission, at the south end of the Warehouse Area.
Chico's Cassette Tape 7: Destroy the Anti-Air Emplacements Side Op. Extract the P.O.W. in the Boiler Room.
Agent's Recording: Classified Intel Aquisition Side-Op. Found in the central watch tower in the Administration Building. Technically you do not have to find the undercover soldier in order to get this. An easy was to get this is to simply stay in the truck that you begin the mission in until it has reached its destination at the Administration Building.
Classified Intel Data: Classified Intel Aquisition Side-Op, when you go to retrieve the Agent's Recording, notice the camera in the room with the tape before you enter. If you radio Miller about it or are caught by it, Miller will mention that this was a setup. Find the undercover agent and make him answer for this deception. He will tell you that the real tape is in the hands of a marine with a shaved head. The marine in question is found down in the boiler room. Sneak up and make him give up the tape.
"Here's to You" Song: Ground Zeroes mission. Located in the cell adjacent to Chico's.
"Resurgence" / "Theme of Tara" Songs: Deja Vu Extra Ops. Located outside the cave on the beach, to the north-east of the insertion point.
Zone of the Enders: The 2nd Runner - Beyond the Bounds: Complete every mission on Hard.
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