My father had one of those, with the “7 Liter Trim” package (Just the trim line, not the engine 
). I drove it to work for two years, and it was extremely reliable, with a really great ride quality.
Of course, the brakes were really poor, but that could be said for virtually all American cars in 1966.
Age 3 ???
I remember the 1955 Chevy sedan that we got when I was but I doubt that I remember the car until a year or two later. I don’t remember the 1949 Nash that my parents traded for the Chevy.
Sounds like a nice neighborhood and a nice bunch of cars. The Buicks would probably be my favorites, thought I myself had a '64 Olds 88 for a few years.
Yes, I was able to start telling some car makes/models apart by age 3. By kindergarten I could identify a lot more, and my dad started to notice and started quizzing me sometimes when we drove. This was in the 1960’s when cars were more distinctive than today.