Well I spend yesterday disassembling the carb, cleaning it up and putting it back together. I'm left with an extra black plastic piece 1 1/2" long and 1 3/4" wide and 1 1/4" high. The "high" is a circle with a 1/2" hole in the middle. I thought it went on the side where the fast idle cam is but it doesn't seem to fit anywhere. There was no picture of it on the rebuild diagram. Anyone knows where it goes or where there is a good "blow up" diagram of the Varijet II. Also, I expose the air mixture screw by taking the "plug out." Do I now saw the carb base perpendicular where the plug was located because now the adjusting screw is deep in the recess?