I have a fuel leak that I cannot seem to stop. It all started when I rebuilt the carburetor. It leaks from the brass fitting that goes into the top of the carb. I've tried everything and it still leaks. Today, I bought a new fitting and put a different carburetor top on that I had lying around. All factors are different than before and I still have the same darn problem. Could it possibly be that the float is set wrong or something. HELP!! (It's a Rochester 1 barrel on a 235 straight six).