Fuel pump pressure

Rebuilt the carb, new float, float valve, new seat and set the float level correctly (triple checked) and the fuel blow still overflows out the overflow. Can you put the pump on wrong, I did pull it off the replace the gasket. Hooked up another tank, above the carb and NO leaks, nothing out the bowl overflow, runs great??? I can hook up a hose and blow into the fuel inlet and rotate the carb and I know the float is seating. Any ideas.

BUD