Use the Spudger tool to get access to the loudspeaker. Locate where the headphone jack is, then move about one-inch to the right and begin to gently pry the back-cover off the phone with the flat end of the Spudger tool. Make sure to pry apart the entire perimeter of the back-cover to prevent bending/cracking of the plastic.

Tools used: Spudger tool (used as a wedge to pry off the back-cover and loudspeaker.)