I'm having the XM radio installed into my AVIC D3 next weekend. I want the installers to use the XM antenna that already came with the truck. Do i need to buy any special items for them to do this or give them any instructions?

2003 Yukon Denali

AVIC D3 with Bluetooth, IPOD controller

If your vehicle came with XM from the factory you should only have to unplug the gm module and plug in the new module. You want to plug the new module into the old antenna. If I remember right you have the dual output antenna, but gm splices it somewhere along the line to make it a single Fakra connector. You may have to do some trimming on the connector to get it to fit the aftermarket XM module though. I just installed a 2007 Tahoe XM antenna on my 2001 Silverado and used the Pioneer 920 module. I just spliced the Pioneer antenna to the factory antenna and it works great.