Buicks had afbs from the factory.
this my buddies car. https://www.hemmings.com/blog/article/1965-buick-gran-sport/
Was one of the 12 best cars in HMC one year a few years ago.
No, his car is not 1000 point original, but IT IS NICE!
4gc where never factory on any engine I know of. wcfbs where on older stuff