When I installed my dual Holley Webers, Tom Langdon told me that I did not need the insulators. Like Dave, no problems with just using the gaskets that came with the carbs. You adjust the choke by loosening the three or four screws on the ring around the choke element. Rotate the choke until it is lightly closed to the carb opening when cold. Then warm up your engine allowing the choke to open normally. You may have to do a slight readjust if it doewn't open completely.

Country Roads, West (By God) Virginia
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