That would explain why the upper vent line fitting on the right side of the carburetor was capped off.

 

Yes if the upper nipple is capped off,there still should be one below it or the other side for the air vent. May have originally had a vent tube with a one way check valve like in the first pic. Can't remember off hand. If you don't have the check valve no big problem.Later models did away with them also.

 

Thanks for all the info!

 

There is 2 vent tubes on the top with a Y connector.

 

Even better... Main thing is that you hook the fuel valve line outlet correctly to the pump inlet,pump outlet goes to the carb, pump vacuum line to the fitting on the carb intake manifold. Once you get it hooked up,you can test the pump condition by pulling the fuel line from the carb and cranking the engine over. Should be a steady or pulsing flow of fuel.