Let's start with the stock manifold followed by the original Ford adapter.  Shown below is the stock 1.5" intake opening on a 1962 170.

Now, the same head with the original Ford carb adapter in place:

Note how the Ford adapter permits coolant to warm the intake charge during cold weather.  This is said to improve fuel atomization and cold weather driveability.  Also note the PCV nipple at the 4-o-clock position on the adapter.  This adapter changes the carburetor mounting points 90 degrees to the engine.

Another angle of the same adapter showing the linkage pivot mounting point.

Generally speaking, the conversion involves the following: either a H/W 5200 or Weber DGV, an adapter mount, and linkage adaptation.  The most commonly used adapters are available from Clifford Performance about $70, and from Stovebolt Engine company, Inc. about $15.  Be sure to check with suppliers for current availability and price.

Before you select your adapter and carburetor, you need to do some homework.  If you have an early Falcon, Mustang, Fairlane, etc. that uses a bellcrank arrangement mounted on the Ford carb adapter, you will have to fabricate your own linkage as no "kit" exists to adapt the stock linkage.  If you have the later style linkage using a one piece arm, then you can easily fabricate an extension to work with this carb or purchase one from Clifford Performance.

On to the carburetors, the Holley/Weber 5200:

And the Weber DGEV:

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