If the carburetor is a Autolite/Motorcraft 4300D (spread bore) there is no direct replacement, replacement will require a change of intake manifolds too.
In my opinion there is no better carb for a stock motor than the 4300D.
A good rebuilder for the 4300 is Pony Carburetors:
http://www.ponycarburetors.com/default.asp
George
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