The basic process is as follows: (You will need a Torx #5 screwdriver and a pocket knife or plastic cellphone opener)
1. Remove the battery cover. Remove the battery.
2. There will be four Torx #5 screws, three blue ones and one silver one that will need to be removed.
3. Then comes the hard part. The top back cover has to be removed. First, use a penknife or xacto knife to take the transparent lens cover off the camera/flash area.
Then, use a plastic cellphone opener or a pocketknife to carefully pry off the top back cover. There is a small amount of adhesive holding the cover to the unit, so start from the bottom and work your way around. There are about four clips holding the back cover onto the unit, and you should feel them snap open. Be careful not to break them off.
4. Once the back cover is off, there will be two more Torx #5 screws at the top that you will need to unscrew. Then use your penknife to carefully pry the unit away from the front faceplate. Start at the bottom and work your way around.
5. There will be a small connector which connects the keyboard to the circuitboard. Carefully disconnect this.
6. The LCD will likely be sitting pretty tight in the LCD lens; use the penknife to carefully pry it off and then transplant it into the new faceplate.
7. There is a small metal box-like apparatus up by the top speaker that also needs to be transplanted from the old faceplate to the new one.
8. Take the old side-buttons and put the in the new faceplate.
9. Connect the keyboard connector from the new faceplate to the circuitboard of the unit.
10. Carefully snap the unit into the new faceplate. Screw in the two top screws. Put the top back cover back on. Put the camera/flash lens cover back on. Screw the four bottom screws back in. Put the battery, SIM card, micro-SD cards back in, and put the battery cover back on.