XCFloresX photography does an awesome job of this mod on a youtube video. Watch his video first!
My instructions are just a specific case for my camera and the 3.5mm jack I chose to use. I have the Asian model not the Rebel.
Make sure you get all the screws out before you remove the back case. The back case comes off quite easy. My camera had a screw hiding below a sticker.
When you take the back cover off be careful not to damage the ribbon attached to the circuit board.
Small Philips screwdriver - make sure it fits properly in the head, these little screw heads will strip out easily.
Small Flat screwdriver - to pry off the back cover.
Hot Knife or a small saw, something cut plastic
Small file or Dremel
3.5 or 2.5 2 pole audio jack