What I think is this.... The insulator block is needed so heat does not soak back into carb after you shut down the engine. If the heat gets to the carb it will perkolate the fuel and restarting will be hard untill carb cools down. Now, when running the carb and intake should be the coolist part/place of engine. The incoming air and fuel does the cooling. Charley what did you have in mind when you said" I would have that carb and block off there in a flash?? You may have a good idea, lets here the rest of the story. Paull Harvey AKA Captinjohn