Unlock code for GM Radios?

GMC Yukon 2003 with Bose system (RDS Head Unit)  Theftlock is on, tring to manually unlock the radio.

How can I unlock A GM radio once is taken out.  The code is supposed to be the last three digits of your VIN#, but what is the procedure in unlocking it?  Does anyone Know this.

first what are you trying to do with radio. if you are putting it back in the yukon it should unlock itself because it is tied to that car. if you are giving it to someone or receiving it from someone, then they/you would have to take it to the dealer and see if the dealer can reprogram it to their/your vin via the databus. but you cannot just take that radio out and put it into another car because that radio tells you everything about the car it came in like tire pressure, xm radio etc. if you are the recipient then it might be cheaper to just get an aftermarket radio because we all know how much dealer prices can be, thats assuming they can do it. i have only heard of it being done once. hope this helps.