GM used air pumps starting in 66, Ford started using them in 67.... Chrysler avoided them until 73......
The single vent line in the trunk tells me the O/P's car is a 49 state car.....
On the tips, I agree most 440-6 & Hemi 71's you see do have tips, a few don't, the California cars aren't supposed to have them but how many guys on the line looking at an obvious performance model coming down the line would have already grabbed an exhaust system with tips, then see the broadcast sheet & it sez no tips... Are you gonna use whats in your hands knowing thats really what the buyer is gonna want, or go back & swap them for the turn downs? Or the car was built with the turndowns but the buyer wants tips, the salesman sez "No Problem, we can put those on".. Or the car is a year old & the owner grabs a set of tips & a color matching rear valance off a wrecked car..