I think you found a BHPD car, and one that isn't on the internet no less. Nice find. No plans on BHPD but maybe it's something you might be interested in?
I believe your source and what you have to say about it. For now I will keep my expectations low and just put one more car in, just like Port Police/Warden because of a lack of references.
For the time being I'll also put more work into FD and EMS (besides the civilian cars) because I feel like there's still a few things that are missing from them.
Previously, I have been aware of airport operations cars for guiding planes and what. It appears to be the same as the black and white but with completely different lighting, livery and setup, This appears to be a Ford Maverick. Based on 11john's info, Security Bureau used the same car as Airport Ops.
Now the mystery deepens: What was used between 1979-1985?