Just in case, there's a little more I can add to help with this.
Heres the connector part # 12193930
These were originally Delphi connectors, but Delphi is now APTIV
http://ecat.aptiv.com/feature?search=12193930
https://www.aptiv.com/suppliers
http://www.terminalsandconnectors.com/Products/Product/12193930
http://www.nusourcetech.com/linecard/Delphi/12193930.php
http://www.1sourcecomponents.com/search/search.htm?base=12193930
https://www.asapsemi.com/rfq.aspx?id=12193930&mfr=delphi
https://www.asap-ittechnology.com/quote/delphi-connection-system/12193930/
https://www.asap-distribution.com/connector/rfq/delphi-fci-automotive/12193930/
http://www.just-connectors.com/rfq/delphi/12193930/
If you need more sites than that,
www.google.com
I found an old write up, that listed mouser, but they are out of stock, and I have not tried to order from any of these links. If anyone tries to order from them, help others by posting up what happened. The one site that is out of stock (Mouser, which is probably out of stock from being listed as the option from another MBEC write up), had them listed at $1.32 each and you could buy one. I have no idea if any of these other sites have a minimum purchase amount, or how much for each. My suggestion if you have to buy lets say a minimum of 25 or 50, would be to also buy enough terminals to include 8-10 each loose and uncrimped, (they are cheap enough in bulk, and easier to find then the connector). Buy some padded mailers, and see how many stamps you need (probably two), and sell them on here cheap. It would probably cost you $2-$3 total shipped. You could put an ad on here (and a Silverado website or two), then sell them for $5 or $10. Link the write up, and this is brought up enough, I would think you could sell them quick with most people buying them just to have this option for the future in case they come up with something.
The pinout is different from the 99-02 to 03-06/07 classic, (and NBS is the only one that uses this connector), but its the same connector and terminals for all NBS years.
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