there should be a hose running from the wiper motor to the upper diaphragm, rear side, then another from the front of the upper diaphragm around to the intake manifold behind the carb. All the pump does is boost the vacuum from the manifold, so plugging the in and out temporarily should be ok. Make sure the vacuum created by the pump is flowing in the right direction, I learned from rebuilding my Buick pump that you can put it together backwards and it will not work.
