which adapter, 07 silverado

I have searched and cant seem to find the excat answer Im looking for so here is what I have .

07 Chevy Silverado new body style with Non Bose radio with Onstar and XM radio. I have an amp and a 10" sub hooked up using a line out converter. Im planning on putting a Pioneer DEH-P710BT radio in. Can I take the line converter out and  and run my rca cables to the pre out in the back of the radio? The only thing im using and amp for is the Sub .

I have been looking at adapters and Im really confused on which one I need to keep the Onstar, XM and all the chimes. Here are 3 I have been looking at                         Pac os-3  , Pac os-4  and   GMOS-LAN-01          Which one will I need to keep everything work properly or is there a different one?

I also was told im going to need a new XM reciever to keep my XM with the aftermarket radio . Is this correct ? Looking at this one .      Pioneer  GEX-P920XM

If you need any other information please let me know

Thanks In advance

Ken

Ok went with the OS-4 . Now I have a wiring question  . The yellow ,red and black wires that you run from the OS-4  to the radio wiring harness run into what looks like a relay can I hook up the yellow, red and black wires from the radio harness to these ? Also the Blue Wire with the white strip what excatly is it for  and does it need to be hooked up ?