need radio plug for pioneer deh 1200mp

I got a Pioneer Deck DEH-1200MP installed it myself in a 2005 GMC Sierra 1500.

I went to find a radio plug for my truck so I could hook it up into the stereo deck and I am having no luck whatsoever. I found an adaptable plug for the GMC Antenna Harness, but it doesnt fit into the Pioneer deck and ~vise versa~.

Do I have to go to Pioneer exclusivley to get what I need? How do I solve this problem?

Please help, I've spent the whole year fixing this truck up and I'm finally down to a couple of repairs now.

Do you have the harness for the radio?  The one that came with the radio, black plug with a red,yellow, black, blue, and 4 sets of speaker wires.

Does the truck have OnStar, or a Bose audio system?

I used the plug that came with the radio, there was only one plug and that just hooks-up the Stereo deck with power and the truck speakers.

The truck doesnt have On-Star, Navigation, Bose, Lasers, satellite scanners, photon torpedo bay or automatic door unlocking systems

Apparently I needed a :

40-GM10 General Motors Antenna Adapter Cable

Made by Metra Antenna Works: 1988-up GM Factroy Antenna with mini barbed or barbless (whatever that means.)

In the cricle it says: Fits New GM Barbless

ANyways I hooked everything up while I was driving and the radio works now, wonderful. Spent $20 bucks at audio express but it was worth it considering ship&handling plus time looking for this thing, there's a few shops in town that have various audio accessories, but none of them were carrying it even though they had big inventories.

Now if i can just fix the speedometer in this jalopy I'm good to go, then I can re-assemble my dash.