All 17xxx VINs are Canadian spec. I think all Canadian cars
left the factory with vent mount antennas. I have never
noticed a vent that looked like it was molded to take an
antenna. I think all of them were cut. And of course some
are cut neater than others. I have VIN 17086 which was
probably two cars down the production line from yours, so
I'll take a look at the vent and see how it looks. Heck,
I'll even take a digital photo of it and put it online.