BCM Help

[Cuse]

I'm a noob to the nbs Tahoes and recently picked up an 03 Z71. I have determined that a new BCM is required. Do the numbers on the replacement BCM have to match the original? There are a lot of these modules available (with many different numbers) for this vehicle , I would hate to spend the money on a replacement only to find out that it is the wrong one. Thanks for any info that may help.