I don't know what other modesl these will work but I just purchased these off eBay and with the exception of a minor modification they work perfectly.

CHEVROLET Cobalt 2006 Speaker Adapter Harness Connector | eBay


I had to trim off a small piece of plastic which acts as a 'key' on the stock speaker plug so it would accept the adapter but other than that the clip and pins snap together for a nice clean fit.

Sorry I don't have pictures of the installation. I'll try to post those. It was worth $20 not to hack up the stock cables.

Other years may also work.

Crutchfield says they don't have any which will work.

I also purchased 2 pairs of speaker harnesses to simplify the installation. NOTE** After installing them I noticed the front speakers cutting out. It turns out these harnesses need another small 'adjustment to work correctly so the pins make a better connection. This was adequate for me but you may choose to pass based on this info.



Mod - Looking at the pins give them a gentle twist with a small pair of needle nose. Twist a bit and try the fit. If you twist too far they may break. Solve my problems.


The stock GM speaker plugs need to have the 'key' trimmed to fit into the harness but the plug 'lock' still works. Simple no solder solution.

I hilighted the portion of the plug which needs trimming with a felt marker

 

those would work with virtually all gm speakers

 

good contribution. I always like posts like this where people are proactive about sharing their experiences with products/solutions that others may not know about.

 

Thanks! I'll try to post a picture of the bit that needs trimming. I need to setup my PhotoBucket to post pictures. When I take the door panels off I will take some photos.

 

Updated picture of portion of speaker plug which needs trimming




The portion hilighted with felt makrer can be removed with a razor knife. The 'plug lock' will still work to hold the plug and harness together.

 

updated