Interesting photos you took there. The 180.949 is the correct engine for these cars, but those smog ports are weird. But interestingly, I read on WIKIPEDIA that the smog (air) pump system was invented in 1966:

https://en.wikipedia.org/wiki/Smog_pump

The system you have described and photographed meets much of the criteria of an early smog air injection system from the late 60s. With that in mind, I suspect it could be original to your vehicle. From what the Wikipedia article states, removing it was a good choice as the operation of the smog pump has been reported to greatly raise EGTs to the point of damaging valves in some engines.

My thought is that the smog pump must have been a 1968-only thing on these vehicles. '68 Fintails are a rare breed, so that could explain why so few are known to have these smog pumps.