Even if you think you have the original carburetor it is best to confirm this with the numbers on the carburetor. Their carburetor is actually a 1976 not a 1977. One year off can make a difference in the kit you need.
Rochester Quadrajet Carburetor Rebuild Kit 79-86 Chevy GMC Olds Pontiac 305 350
Rochester Quadrajet Carburetor Rebuild Kit w/ Float 79-86 Chevy GMC Olds Pontiac
Rochester Quadrajet Carburetor Rebuild Kit w Float Filter 1978 1979 Chevy 4 bbl
Rochester Quadrajet Carburetor Rebuild Kit 1979 - 85 Chevy GMC Truck 4 bbl 15753
Rochester Quadrajet Carburetor Rebuild Kit Float & Filter HD Pump 75 - 80 Chevy
Rochester Quadrajet Carburetor Rebuild Kit w Brass Float & Filter 75 - 80 Chevy
