What is the best carburetor to replace the factory carb on a 1965 thunderbird?
Why are you wanting to replace the factory unit?
Because it is junk.
Then your best bet is Holley, make sure you get the one with the correct heater for the choke and the proper throttle arm for the automatic.
Why do you say it is junk? Is the car running? Did you try to overhaul it and mess it up? Some more details please. Yes, the Holly is probably your best bet if replacement is your only answer.
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