I have a 1966 442 four speed carburetor # 7026250 . I'm trying to get ported vacuum for my stock distributor and only have one port on carb which is full vacuum. Does any one know where the correct port is for distributor advance?

 

You could use a manifold vacuum source instead of ported vacuum. That is how I have mine set up. Try it and see how it runs - you may like it better that way.