carb install

[rugger]

I have a couple of questions regarding my carb install. It is off of an 82 305 and is a rochester Qjet. I can figure out all of the vacuum connections but can't fugure out what the large threaded input is at the back on the bottom. Can anyone show a pic of the back of a similar carb? Is there supposed to be a plug in this port? My second question is about the fuel pump. I have the line going to the carb but there is an extra output on this too. Does this connect to the back of my carb? The old engine was a 292 1 barrel so the fuel system is still set up for that truck.