Lonnie,
You are, of course, correct about no gaskets being mentioned in the Shop Manual.
In the purist's tradition, I have tried it with no gaskets. Usually, I have had leaks between the carb and the insulator, so I now always use a gasket there. Most of the time I get away with no gasket between the bottom of a smooth insulator and the top of a smooth intake manifold.
Just in case someone reading this does not know, there are notches in the gasket, one of which should line up with a vacuum hole/port in the base of the carburetor - this notch must line up with that hole in the base of the carburetor.
The original phenolic spacers/insulators had notches in them. Some replacement insulators do not have the notches in them - a correctly orientated gasket must be used with this type of reproduction insulator.
