Where can I buy a Deanli touch screen navigation system by Delphi other than ebay?

I have an o5 GMC Sierra Z71 with the bose system, so I dont know which one I should buy. Anyone have the hookups at a GM dealership?

 

do what I did, head to a local stereo shop that does dealer work....They are always willing to sell you the take outs.

 

Problem is finding one of those shops? Do you think that the dealer will actually provide me with the name of a shop that they use?