The iphone 4 backlight IC is the same used for the 4th gen Ipod Touchs and is the same one also used for the 32gb and 64gb 3rd generation Ipod Touches as well. Be carefull when you take the EMI shielding up on the circuit board because Apple uses independent grounding system and uses the EMI shield to connect the grounding nodes around the edges of the circuit board together. It may run without it on, but now your in violation of FCC regulations and if there is a static discharge internally in the ipod the circuit board is at risk because it is not properly grounded.
My suggestion is using a Soldering Iron and Chemi-wik to remove the solder that attaches the EMI shield to the circuit board. This way when you are down removing the old IC and replacing it you can re-secure the shield back to the circuit board.
Just an idea of correct tools if you do this a lot. I use a Hakko FX-951 and FM202 soldering station with controlled heat and interchangeable tips for different applications. Resin Solder and water-soluble solder are in common use but with the correct techniques. All of these can be found on eBay.
-Adam