Radio replacement in a Express 3500 2009 passager
 

Hi all chevy expert!
I whant to change my OEM Radio for a double Din DVD Pioneer Deck.
To keep the door chime, signal sound and warning beep, i think i need a Adaptor. Do you think I only need this:

GM Factory Integration Adapter GM Class II Data bus Interface at Crutchfield.com

Some other site tell my that I need this big one:
GM Onstar GMOS-LAN-01 LAN Data Bus Interface

I do not have OnStar truck.
I think I need a FM antenna converter too. But I can found the right one.
Can you help me?
Thanks

If you do not have onstar, the "simple" chime module should work.

I used Metra Online in my '07.
Retained all chimes except seat belt chime (darn it!)