McIntosh 1700 receiver question

Just picked up one of these and am confused about the speaker tie in. The receiver is one of the early models. It has the screw speaker connections. They are vertical with NO NOTATION as to what they are. I want to connect a vintage set of JBL speakers to it but cant tell how. Any help would be appreciated.

I have one of these as well. The silk screen marking says "left" over the left column (vertically oriented speaker terminals) and "right" over the right column. The lower connections are marked "common." Hope this helps.

Bob R.