Alright, just to put this out there:

ANY 00-02 Silverado-style cluster will interchange on 00-02 trucks without reprogramming. Only in exceedingly rare occasions will the cluster need an ACDelco reprogram.

ANY 03-07 cluster requires package programming to match the target vehicle. If you have something that isn't programmed, or something is programmed that doesn't exist, the cluster WILL go cuckoo. Stuff like steering wheel control type, Bose/No Bose radio, Memory Seat & Mirror types, etc.

Also, the 03-07 cluster needs to be programmed by VIN by an ACDelco programmer to ensure proper package programming. If you succeed in an unprogrammed swap, then most likely both vehicles were equipped with identical systems.

 

good info