As to original carbs on the 302:

G.M.C. used Holley type AA-1, Stromberg type WW, and Zenith types 263 and 885.

The type 263 is a single barrel (size 4).

The others are 2 barrels.

Jon

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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