Guys, you're all bringing up valid points, but you've missed the biggest point of them all. This is just a suggestion. There are lots of kinks to work out, but wouldn't you want the option of a different powerplant? Everyone is complaining about the lack of Z28, but some of those same members enter this thread criticizing an idea that could provide the same options. It's as if you want a badge more than you want a fast car. If you want the badge so badly,
here you go.
Now, a few of you have argued that this is impossible for a variety of reasons. There are simple solutions for most of these problems, so I will itemize them.
Safety
This car would have to be safe. In order to do that GM would do crash testing to verify that it met safety standards. That wasn't so hard. Let's move on.
Emissions
The technicality requires that this be a car different from the Camaro. In essence, GM must rebadge it as something else in order to minimize the cost of production. GM does own a variety of names known for performance that would suffice for such a product that would see substantially lower production than the Camaro. What was the name of that storied brand that GM killed with a history of performance vehicles?

Make the car a special order with limited production available at select GM dealers.
Production
This section is negotiable. I just thought this was a good idea. Production would be limited to a low enough number that the EPA and other applicable agencies would not emissions test it. GM builds a car on the assembly line with all the other cars. GM does not install the engine or the transmission. GM ships the car, engine, and transmission to a dealer. The dealer installs the custom parts. Continue this story in the next section.
Sales
The dealer has just paid a bunch of labor in the process of putting together the car. Now, the dealer sells the car at a high enough price to pay for that and get a profit. Why would I suggest this? Dealers need an incentive to order the car. For this reason, these custom products would have to be worthy of markups. If we don't give dealers an incentive to order this, no one would have one, and that would suck.
Matching Numbers
There's been such a negative response to this idea that you can forget I mentioned it.