1968-'71 were bayonet. Some very late '71 cars may have been built with bolt-on sticks, but most of what I've encountered that appeared unmodified has been bayonet... and let's be real, who would intentionally downgrade from a bolt-in stick?
The pilots exist on OEM shifters to drill for stop bolts:
It's very easy and a popular modification, even in "the day" so to speak. With these parts being so old, it's impossible to say what a previous owner did to something. The easy way to tell if the stop bolts are original is to look at the area around the hole. Hurst stamped those holes, they didn't drill them. The non-OEM Hurst shifters I have show a slight depression around the stop bolt holes from the stamping process.