03 Chevy Truck

A friend asked me if I could install a CD player in his new company truck.  I heard that the 03 chevy truck's require special wiring.  Is this true?  Right now the truck has a factory cassette deck. 

Thanks for any help

I did not see the radio just yet but I think it is a basic system

I installed the new CD player in the 03 Chevy truck without a problem.  In my area none of the car stereo shops knew anything about the new chevy trucks.  I purchased a wiring harness and a dash kit from a national chain stereo store.  Well to start off the wiring kit was opened and the dash kit was for the wrong year.  After three trips to the same store and a phone call to metra I have it working.  The first wiring harness that I bought required that a seperate 12 volt switched lead be run from the fuse box.  Then the factory radio would have to be relocated under the seat.  This is because of the door chime.  I was told that some chevy vehicles uses the radio to send data for the door chime and other warning signals.  Well I then purchased another metra product that does not require a seperate switch lead or relocating the factory radio to remain in the vehicle.  The cost of the harness was $60.00 but it was worth the money.  I hope that this info helps anyone with their future installs of chevy vehicles.