GM Navigation in a 2006 GM Sierra

[Hermosa]

Just installed a GM factory Nav unit in my 2006 Sierra that I just pulled from my friends 2005 Yukon. When installed, it came up with "Theft Lock". Is my only choice to bring it to the dealer to be unlocked, and how involved is that process?
Any info appreciated!

[It's all Good]

I think that is the easiest way to get it done. The Chevy Avalanche forum has a ton of information on getting it done. This guy in Michigan can also do it for you, machomachodan@yahoo.com.
Dealer Unlock instructions (http://www.chevyavalanchefanclub.com/cafcna/index.php/topic,44768.msg702956.html#msg702956)