That round plastic cover on the side of the carb is the choke and if memory serves me right, it was set on two rich. From your pics it looks like the previous owner disabled it and added a manual choke.
Try hooking that loose vacuum line to the line on the side of the carb near the choke.
As for the two ports in the back of the new carb, I only remember one and it was blocked off with a rubber cap.
Good luck.