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 1973 not a 1975. One year off can make a difference in the kit you need.
Rochester Quadrajet Carburetor Rebuild Kit w Float Filter HD Pump 72 - 78 CHEVY
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 Float Filter 85 - 86 Chevy 6 & 8 cyl
Rochester Quadrajet Carburetor Rebuild Kit w Float Filter 1978 1979 Chevy 4 bbl
Rochester Quadrajet Carburetor Rebuild Kit Brass Float & Filter 1972 Chevy 350"