I was recently involved in this discussion about the change of location of the mat-securing hooks in "late" '13 'Vettes:
In that thread I recount how I was told by Patrick at GMPartswarehouse.com that those hooks can be moved if they are not in the right position.
I finally found some time to install my mats, so I thought I'd document what I did in a new thread in the hope that others with this problem will be able to find it easily.
The hooks are indeed easy to remove-- once you know how they work. I bumbled around and got mine out, but when you see how they work it makes it much easier to see how to do it and they'll come out in about two seconds.
As you can see, you can just use a small screw driver to release the clip and slid it out:
I then cut two slits with a razor blade in order to move the hook about an inch outboard. The arrows indicate where the slits are cut and, as you can see, slits in carpet are pretty much invisible:
Here's the hook installed in that new slit (the factory slit is crooked-- I installed it straight thus there is an angle between the current placement and the old):
And here's the mat on the newly-placed hook-- nice and centered:
Although there was little doubt, GMPartswarehouse had the right info.
So if anyone has any hooks that are not optimally aligned they can very easily be moved.
Thanks to Patrick for the advice and good luck to everyone trying to get their mats to fit!