Will the Holley 350 cfm fit on the stock manifold ?

No.

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“Buy the ticket, take the ride.”
― Hunter S. Thompson

But there are $20ish adapter plates to mount the 2-barrel Holley on the 2-barrel Super Six manifold. (Hint for adapter shopping: The Rochester 2GC uses the same bolt pattern as the Carter BBD.)

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Somehow I ended up owning three 1964 slant six A-bodies. I race one of them.
Escape Velocity Racing

Somewhere on this board used to be my build up. I took a Super Six intake, laid a Motorcraft 2100 gasket on it (same gasket as the Holley 350 carb), and spray painted it. Then I removed the gasket and whatever was John Deer green needed to be cut away. I drilled a series of 1/8" holes around the edges of the green, whacked it with a hammer, and it all broke free. I smoothed it out with a Dremel, slapped an adapter made from 1/2" aluminum plate on it with countersunk bolts, and called it a day. Been working great since 2008.

Or you can get the already built adapter Space Frank suggested. My method just lined up the throttle bores a bit better.

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If it was easy, everybody would be doing it.