I bought the 2010 Camaro driveshaft-to-differential coupler kit to try to save some green, but it's not completely identical. The bolts will all slip through, but the ferrules pressed into the coupler aren't designed to sit into the yoke on either the driveshaft or diff like the G8 part is.
Pictures!
Here's the two of them side by side. Camaro part is on the right. If I flip the Camaro part over, you wouldn't be able to tell them apart.
You can see that the ferrules on the Camaro part on the right are bigger.
Now, on the car, here's the original. You can see it sits pretty much flush. This is because there are indents in the diff yoke that catch the protruding ferrules on the coupler and align it.
But with the Camaro part in the same spot...
You can see the ferrules don't sit into the yoke, meaning that the coupler doesn't quite lock into the yoke in the same way.
Now, in reality, I'm trying to mount the Camaro part backwards here. Thick grade 12 bolts are provided with the coupler kit and, in the Camaro factory service manual, those bolts go through the driveshaft yoke which, on the Camaro, isn't designed to seat onto the ferrules of the coupler. The coupler ferrules do still seat into the differential yoke on the Camaro. On the G8 part, the ferrules on both sides seat into the driveshaft and diff yokes.
So if I still use the Camaro part, I'll seat the ferrules into the diff yoke and the driveshaft yoke will just bolt through.
So my concern is thus: do those protruding ferrules actually take any serious amount of the shear force of use off the bolts such that I am risking shearing them or breaking the driveshaft yoke if I use a coupler without that ferrule lip?