In 1964 I was 13 and pumped that my parents bought a new 1964 Grand Prix. The engine, a 389 4 bbl, is essentially the same as the 64 Bonneville. The "Robins Egg Blue" that I see in this thread is correct. The air cleaner will be a semi gloss black and it will have one "snorkel" that should be positioned not straight ahead but at an angle facing the passenger side of the car.
Hope this helps. Loving your build project.