Where to Drill..? Emergency Brake

[amcgeh01]

Hi All, Hoping someone out there might have a pic showing the empty firewall where the emergency brake assembly would normally go...?

Apparently the body guy took it upon himself to fill in most of the holes and now I cannot tell where the assembly goes exactly other than guesstimating. Here are the pics.. I can see an outline of a small square where I think it might go but not confirmed since it's all metal now. Obviously I don't want to ruin the paint job either by drilling multiple holes...

Also, on a side note.. Since I have no emergency brake setup at all, no hangers, clips, connectors, etc.. What is the best way to go about replacing it all.. I recently installed a rear disc brake conversion from Auto City Classic, (https://www.autocityclassic.com/chev...-rearc106ltrk/) and it went in fine but then I started thinking how am I going to connect the original system to it once I get it. I see that Inline Tube makes a complete kit but has anyone used it and will it work in my situation...(1969-72 Chevrolet GMC Truck Parking Brake Cable Set Kit OEM 1/2 ton 4wd BST6944) Just curious to see what folks are using before I buy something.