The lower port will lower pressure with vacuum and raise pressure with boost (forced induction)

The upper port (near fuel lines) will raise pressure under vacuum, and lower pressure with boost.?

Lower WUR pressure = richer. Higher WUR pressure = leaner.?

You should have a vacuum diagram on the underside of your hood which will tell you which port should be connected to which.?

However, under vacuum you want it to raise the pressure so when vacuum is removed it gets richer for better response. So top port is where the vacuum is likely to be. Lower port is unlikely to be used, but if it is, it would likely be connected to the same port for vacuum advance or to receive partial vacuum during accel. It won't be connected to manifold vacuum.?

Cheers