EGR vacuum control switch

1973 Dodge Dart 318 cal version has 2 ports on the firewall side but all my ligature research only shows me 1 port set up on the switch.
Looks like one hose would go to the vacuum Amplifier port, if so would it go onto the top or bottom port on the vacuum switch on the firewall

another photo shows the EGR valve hose going to the vacuum amplifier

I'm lost on this one