This is a 1966 Buick intake manifold #1372133 with 1966 Quadrajet carb #7041309. This is a one year only set up that was found on the 1966 GS400 which was a 401 with this intake/carb. This set up could also be found on the 425, but I believe had a different serial number.
The carb was completely restored by Carmen Faso in New York. Those close to the Buick community know Carmen and the quality of work that he does.
I ran this on my Wildcat for a few years and have now moved on. The carb is still very clean and the intake has a fresh coat of paint.
Please reach out for any questions.