Temp control cable removal?

So, I'm pulling the dash out of my '67 Valiant and the only remaining hang-up is the cable that runs from the temp control lever on the climate controls to the box mounted on the firewall. My old Chilton's manual says to remove the cable at the firewall end, but I can't figure out how to get either end disconnected. This is probably a very noob question, but how the hell does this thing come apart?