What I would do is buy the Holley Carb right for your car, NEW.
First of all you need a 600-650 CFM Max, I like the vacuum secondaries also on a street car.
I am sure you could rebuild something to work OK but with the price of a new performance Holley (Proform, Quick Fuel) carburetor in the 500.00 range it sure cuts out a lot of problems.
Used a Quick Fuel Tech. 650 , vacuum secondary on Juan's car, out of the box it has been great, just adjust the float level and drive.
Nothing worse than problems with a carburetor, my 2 cents worth.
Rick
427 S/C , 427 Side-oiler, 4 Speed Close Ratio Top Loader, 3:73 Gear
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