Score! They should bolt right up!

 

Here are the calipers!

 

You have the mount brackets there but I don't see an emergency brake set up, could you take a couple of pictures of the back side of the rear rotors, please

 

Hmm. Those rears seem to be a lot different than the ones on my SS.

The silver painted part is the mounting bracket.

 

Yes your SS mount bracket is almost if not identical to the LS front caliper bracket for the 10.65 inch discs George.
The Cobalt SS Brembo set up was different as the tears are 11 plus inch discs and I think drum style ebrakes

 

Yeah, my SS has the same rear calipers as you do George. Hopefully these will bolt right up. Here is the rear rotor.