I realize this is a pretty common problem. I've tried reading some of the other threads on this site for ideas, but still no luck.
I have a 1985 W123 300D. In the inside of the car, there's just a cable sticking out near where the emergency brake is. As suggested, I have tried pulling on the cable with grips while someone else is in the front trying to open the hood. The other person is pulling out that plastic tab while I'm pulling on the cable, but it still won't budge. I can hear a click somewhere in the front when I pull the cable in and out, but it doesn't seem to make a difference. I thought that pulling the cable would make the plastic tab come out, but we still have to pull the tab out ourselves. I can even see behind the grill that pulling the tab causes a latch to move, but we still can't get the hood up.

Any ideas on what's going on?