Whic way does gasket go on cartet fuel pump

I opened up a carter m4862 fuel pump to see if the diaphram was still good. It looked good so I put it back together and installed it, but it won't pump. It was sitting on a shelf for a bit. There is a gasket that can go on two ways. One way will expose one valve and the other way will expose two valves. Do you know which way it goes?
Thx
Author: 68charger440