Parking Brake Assembly

I'm hoping someone here can help. First, we're talking about a 73 Dart Sport 340, with a manual trans. When I bought the car, the interior was pretty much stripped so I'm accumulating and assembling a little at a time. My current issue is with the Parking Brake lever. I've managed to accumulate what I thought were all the parts I needed. When I got it all assembled and pulled it out to set the parking brake, the handle ends up against the dash. The pull on the cable is causing the assembly to pivot some, driving the back (firewall end) down and the front (handle end) up. Looking at the manual, it looks like there is supposed to be a bolt on clamp that holds the cable in place where it comes through the firewall. When I'm looking under the dash, I don't see any place where the clamp could attach so I'm wondering if there's a bracket that is supposed to be under there that I'm missing. I also don't see where the parking brake light actuator bolts to, so I'm wondering if that's related.
Thanks in advance for any help.