Wanna see how an iPhone 3GS is cracked open?

 

"There are three cables holding the LCD and digitizer to the rest of the logic board. Disconnecting them is as easy as 1-2-3.
• 1: LCD panel
• 2: Digitizer
• 3: Ear speaker  "

If you wanna know more about what's inside your iPhone 3GS, click here.