2008 Impala radio swap

I recently got a 2008 Impala from my employer as a company car. Since it was a fleet vehicle, it came with the AM/FM radio instead of the XM/MP3 radio that would normally be standard on this car. I want to get the XM unit for my car. I feel confident I could install the unit myself, and I've found a couple parts suppliers who sell the actual part, but I've heard I would need to have a dealer unlock the radio for use in my car. Is this true? In addition, I would need to swap the radio back once my lease is up. Would I need to have a dealer unlock the original radio again when I reinstall it? Any answers, or other tips are welcome. Thanks in advance.

You might try contacting customer service at Crutchfield (www.crutchfield.com). They have knowledgeable staff and have answered some questions I have had over the years concerning my vehicles.